diff --git a/src/daos/impl/redis/capacity_dao_redis_impl.js b/src/daos/impl/redis/capacity_dao_redis_impl.js
index 58a8e33..35a16d5 100644
--- a/src/daos/impl/redis/capacity_dao_redis_impl.js
+++ b/src/daos/impl/redis/capacity_dao_redis_impl.js
@@ -67,7 +67,7 @@ const getRank = async (siteId) => {
   // START Challenge #4
   const client = redis.getClient();
 
-  const result = await client.zrankAsync(
+  const result = await client.zrevrankAsync(
     keyGenerator.getCapacityRankingKey(),
     `${siteId}`,
   );
diff --git a/src/daos/impl/redis/feed_dao_redis_impl.js b/src/daos/impl/redis/feed_dao_redis_impl.js
index 253bd40..bbc0aaa 100644
--- a/src/daos/impl/redis/feed_dao_redis_impl.js
+++ b/src/daos/impl/redis/feed_dao_redis_impl.js
@@ -1,10 +1,8 @@
 const redis = require('./redis_client');
 const keyGenerator = require('./redis_key_generator');
 
-/* eslint-disable no-unused-vars */
 const globalMaxFeedLength = 10000;
 const siteMaxFeedLength = 2440;
-/* eslint-enable */
 
 /**
  * Takes an object and returns an array whose elements are alternating
@@ -125,6 +123,8 @@ const insert = async (meterReading) => {
   const pipeline = client.batch();
 
   // START Challenge #6
+  pipeline.xadd(keyGenerator.getGlobalFeedKey(), 'MAXLEN', '~', globalMaxFeedLength, '*', ...fields);
+  pipeline.xadd(keyGenerator.getFeedKey(meterReading.siteId), 'MAXLEN', '~', siteMaxFeedLength, '*', ...fields);
   // END Challenge #6
 
   await pipeline.execAsync();
diff --git a/src/daos/impl/redis/metric_dao_redis_impl.js b/src/daos/impl/redis/metric_dao_redis_impl.js
index e3bb12a..1b77ace 100644
--- a/src/daos/impl/redis/metric_dao_redis_impl.js
+++ b/src/daos/impl/redis/metric_dao_redis_impl.js
@@ -41,7 +41,6 @@ const extractMeasurementMinute = (measurementMinute) => {
   };
 };
 
-/* eslint-disable no-unused-vars */
 /**
  * Insert a metric into the database for a given solar site ID.
  * This function uses a sorted set to store the metric.
@@ -59,9 +58,12 @@ const insertMetric = async (siteId, metricValue, metricName, timestamp) => {
   const minuteOfDay = timeUtils.getMinuteOfDay(timestamp);
 
   // START Challenge #2
+
+  await client.zaddAsync(metricKey, minuteOfDay, formatMeasurementMinute(metricValue, minuteOfDay));
+  await client.expireAsync(metricKey, metricExpirationSeconds);
+
   // END Challenge #2
 };
-/* eslint-enable */
 
 /**
  * Get a set of metrics for a specific solar site on a given day.
diff --git a/src/daos/impl/redis/site_dao_redis_impl.js b/src/daos/impl/redis/site_dao_redis_impl.js
index b3ae30f..1149c5e 100644
--- a/src/daos/impl/redis/site_dao_redis_impl.js
+++ b/src/daos/impl/redis/site_dao_redis_impl.js
@@ -88,7 +88,6 @@ const findById = async (id) => {
   return (siteHash === null ? siteHash : remap(siteHash));
 };
 
-/* eslint-disable arrow-body-style */
 /**
  * Get an array of all site objects.
  *
@@ -96,10 +95,28 @@ const findById = async (id) => {
  */
 const findAll = async () => {
   // START CHALLENGE #1
-  return [];
+  const client = redis.getClient();
+
+  const siteIds = await client.smembersAsync(keyGenerator.getSiteIDsKey());
+  const sites = [];
+
+  for (const siteId of siteIds) {
+    /* eslint-disable no-await-in-loop */
+    const siteHash = await client.hgetallAsync(siteId);
+    /* eslint-enable */
+
+    if (siteHash) {
+      // Call remap to remap the flat key/value representation
+      // from the Redis hash into the site domain object format,
+      // and convert any fields that a numerical from the Redis
+      // string representations.
+      sites.push(remap(siteHash));
+    }
+  }
+
+  return sites;
   // END CHALLENGE #1
 };
-/* eslint-enable */
 
 /* eslint-disable no-unused-vars */
 
diff --git a/src/daos/impl/redis/site_geo_dao_redis_impl.js b/src/daos/impl/redis/site_geo_dao_redis_impl.js
index f703e00..05998bc 100644
--- a/src/daos/impl/redis/site_geo_dao_redis_impl.js
+++ b/src/daos/impl/redis/site_geo_dao_redis_impl.js
@@ -114,20 +114,24 @@ const findAll = async () => {
   const siteIds = await client.zrangeAsync(keyGenerator.getSiteGeoKey(), 0, -1);
   const sites = [];
 
-  for (const siteId of siteIds) {
-    const siteKey = keyGenerator.getSiteHashKey(siteId);
+  // OPTIONAL BONUS CHALLENGE: Optimize with a pipeline.
+  if (siteIds.length > 0) {
+    const pipeline = client.batch();
 
-    /* eslint-disable no-await-in-loop */
-    const siteHash = await client.hgetallAsync(siteKey);
-    /* eslint-enable */
+    for (const siteId of siteIds) {
+      pipeline.hgetall(keyGenerator.getSiteHashKey(siteId));
+    }
 
-    if (siteHash) {
+    // Get all of the site hashes in a single round trip.
+    const siteHashes = await pipeline.execAsync();
+
+    for (const siteHash of siteHashes) {
       // Call remap to remap the flat key/value representation
       // from the Redis hash into the site domain object format.
       sites.push(remap(siteHash));
     }
   }
-
+  // END OPTIONAL BONUS CHALLENGE
   return sites;
 };
 
@@ -178,9 +182,8 @@ const findByGeo = async (lat, lng, radius, radiusUnit) => {
  * @returns {Promise} - a Promise, resolving to an array of site objects.
  */
 const findByGeoWithExcessCapacity = async (lat, lng, radius, radiusUnit) => {
-  /* eslint-disable no-unreachable */
   // Challenge #5, remove the next line...
-  return [];
+  // return [];
 
   const client = redis.getClient();
 
@@ -205,6 +208,15 @@ const findByGeoWithExcessCapacity = async (lat, lng, radius, radiusUnit) => {
   const sitesInRadiusCapacitySortedSetKey = keyGenerator.getTemporaryKey();
 
   // START Challenge #5
+  setOperationsPipeline.zinterstore(
+    sitesInRadiusCapacitySortedSetKey,
+    2,
+    sitesInRadiusSortedSetKey,
+    keyGenerator.getCapacityRankingKey(),
+    'WEIGHTS',
+    0,
+    1,
+  );
   // END Challenge #5
 
   // Expire the temporary sorted sets after 30 seconds, so that we
@@ -248,7 +260,6 @@ const findByGeoWithExcessCapacity = async (lat, lng, radius, radiusUnit) => {
   }
 
   return sitesWithCapacity;
-  /* eslint-enable */
 };
 
 module.exports = {
diff --git a/src/daos/impl/redis/sitestats_dao_redis_impl.js b/src/daos/impl/redis/sitestats_dao_redis_impl.js
index 65df024..3b0a6f1 100644
--- a/src/daos/impl/redis/sitestats_dao_redis_impl.js
+++ b/src/daos/impl/redis/sitestats_dao_redis_impl.js
@@ -43,7 +43,6 @@ const findById = async (siteId, timestamp) => {
   return (response ? remap(response) : response);
 };
 
-/* eslint-disable no-unused-vars */
 /**
  * Updates the site stats for a specific site with the meter
  * reading data provided.
@@ -59,9 +58,19 @@ const updateOptimized = async (meterReading) => {
   await compareAndUpdateScript.load();
 
   // START Challenge #3
+  const transaction = client.multi();
+
+  transaction.hset(key, 'lastReportingTime', timeUtils.getCurrentTimestamp());
+  transaction.hincrby(key, 'meterReadingCount', 1);
+  transaction.expire(key, weekSeconds);
+
+  transaction.evalsha(compareAndUpdateScript.updateIfGreater(key, 'maxWhGenerated', meterReading.whGenerated));
+  transaction.evalsha(compareAndUpdateScript.updateIfLess(key, 'minWhGenerated', meterReading.whGenerated));
+  transaction.evalsha(compareAndUpdateScript.updateIfGreater(key, 'maxCapacity', meterReading.whGenerated - meterReading.whUsed));
+
+  await transaction.execAsync();
   // END Challenge #3
 };
-/* eslint-enable */
 
 /* eslint-disable no-unused-vars */
 /**
@@ -106,5 +115,5 @@ const updateBasic = async (meterReading) => {
 
 module.exports = {
   findById,
-  update: updateBasic, // updateOptimized
+  update: updateOptimized, // updateBasic
 };
diff --git a/src/daos/impl/redis/sliding_ratelimiter_dao_redis_impl.js b/src/daos/impl/redis/sliding_ratelimiter_dao_redis_impl.js
index 0a445c1..96497b2 100644
--- a/src/daos/impl/redis/sliding_ratelimiter_dao_redis_impl.js
+++ b/src/daos/impl/redis/sliding_ratelimiter_dao_redis_impl.js
@@ -1,21 +1,42 @@
 const redis = require('./redis_client');
-/* eslint-disable no-unused-vars */
 const keyGenerator = require('./redis_key_generator');
 const timeUtils = require('../../../utils/time_utils');
-/* eslint-enable */
-
-/* eslint-disable no-unused-vars */
 
 // Challenge 7
 const hitSlidingWindow = async (name, opts) => {
   const client = redis.getClient();
 
   // START Challenge #7
-  return -2;
+  const key = keyGenerator.getKey(`limiter:${opts.interval}:${name}:${opts.maxHits}`);
+  const now = timeUtils.getCurrentTimestampMillis();
+
+  const transaction = client.multi();
+
+  const member = `${now}-${Math.random()}`;
+
+  transaction.zadd(key, now, member);
+  transaction.zremrangebyscore(key, 0, now - opts.interval);
+  transaction.zcard(key);
+
+  const response = await transaction.execAsync();
+
+  const hits = parseInt(response[2], 10);
+
+  let hitsRemaining;
+
+  if (hits > opts.maxHits) {
+    // Too many hits.
+    hitsRemaining = -1;
+  } else {
+    // Return number of hits remaining.
+    hitsRemaining = opts.maxHits - hits;
+  }
+
+  return hitsRemaining;
+
   // END Challenge #7
 };
 
-/* eslint-enable */
 
 module.exports = {
   /**
diff --git a/src/daos/site_dao.js b/src/daos/site_dao.js
index c1e915c..9de4f21 100644
--- a/src/daos/site_dao.js
+++ b/src/daos/site_dao.js
@@ -1,7 +1,7 @@
 const daoLoader = require('./daoloader');
 
-// Week 3, change this from 'site' to 'site_geo'.
-const impl = daoLoader.loadDao('site');
+// Change 'site_geo' to 'site' to revert to using 'site_dao_redis_impl.js'.
+const impl = daoLoader.loadDao('site_geo');
 
 module.exports = {
   /**
diff --git a/tests/capacity_dao_redis_impl.test.js b/tests/capacity_dao_redis_impl.test.js
index ae9666d..292c69a 100644
--- a/tests/capacity_dao_redis_impl.test.js
+++ b/tests/capacity_dao_redis_impl.test.js
@@ -118,7 +118,7 @@ test(`${testSuiteName}: getReport`, async () => {
 });
 
 // This test is for Challenge #4.
-test.skip(`${testSuiteName}: getRank`, async () => {
+test(`${testSuiteName}: getRank`, async () => {
   // Create some data
   const entries = [
     {
diff --git a/tests/feed_dao_redis_impl.test.js b/tests/feed_dao_redis_impl.test.js
index 55991f1..327583c 100644
--- a/tests/feed_dao_redis_impl.test.js
+++ b/tests/feed_dao_redis_impl.test.js
@@ -86,19 +86,19 @@ const insertAndReadBackFromStream = async (siteId) => {
 };
 
 // This test is for Challenge #6.
-test.skip(`${testSuiteName}: insert and read back from global stream`, async () => {
+test(`${testSuiteName}: insert and read back from global stream`, async () => {
   await insertAndReadBackFromStream();
 });
 
 // This test is for Challenge #6.
-test.skip(`${testSuiteName}: read stream for site that does not exist`, async () => {
+test(`${testSuiteName}: read stream for site that does not exist`, async () => {
   const meterReadings = await redisFeedDAO.getRecentForSite(-1, 100);
 
   expect(meterReadings.length).toBe(0);
 });
 
 // This test is for Challenge #6.
-test.skip(`${testSuiteName}: insert and read back from site specific stream`, async () => {
+test(`${testSuiteName}: insert and read back from site specific stream`, async () => {
   await insertAndReadBackFromStream(998);
 });
 
diff --git a/tests/metric_dao_redis_impl.test.js b/tests/metric_dao_redis_impl.test.js
index 814f8e9..f78a990 100644
--- a/tests/metric_dao_redis_impl.test.js
+++ b/tests/metric_dao_redis_impl.test.js
@@ -78,12 +78,12 @@ const testInsertAndRetrieve = async (limit) => {
 };
 
 // This test is for Challenge #2.
-test.skip(`${testSuiteName}: test 1 reading`, async () => testInsertAndRetrieve(1));
+test(`${testSuiteName}: test 1 reading`, async () => testInsertAndRetrieve(1));
 
 // This test is for Challenge #2.
-test.skip(`${testSuiteName}: test 1 day of readings`, async () => testInsertAndRetrieve(60 * 24));
+test(`${testSuiteName}: test 1 day of readings`, async () => testInsertAndRetrieve(60 * 24));
 
 // This test is for Challenge #2.
-test.skip(`${testSuiteName}: test multiple days of readings`, async () => testInsertAndRetrieve(60 * 70));
+test(`${testSuiteName}: test multiple days of readings`, async () => testInsertAndRetrieve(60 * 70));
 
 /* eslint-enable */
diff --git a/tests/site_dao_redis_impl.test.js b/tests/site_dao_redis_impl.test.js
index f60b922..e3d936e 100644
--- a/tests/site_dao_redis_impl.test.js
+++ b/tests/site_dao_redis_impl.test.js
@@ -153,7 +153,7 @@ test(`${testSuiteName}: findById with missing site`, async () => {
 });
 
 // This test is for Challenge #1.
-test.skip(`${testSuiteName}: findAll with multiple sites`, async () => {
+test(`${testSuiteName}: findAll with multiple sites`, async () => {
   const sites = [{
     id: 1,
     capacity: 4.5,
@@ -206,7 +206,7 @@ test.skip(`${testSuiteName}: findAll with multiple sites`, async () => {
 });
 
 // This test is for Challenge #1.
-test.skip(`${testSuiteName}: findAll with empty sites`, async () => {
+test(`${testSuiteName}: findAll with empty sites`, async () => {
   const sites = await redisSiteDAO.findAll();
   expect(sites).toEqual([]);
 });
diff --git a/tests/site_geo_dao_redis_impl.test.js b/tests/site_geo_dao_redis_impl.test.js
index 72bb8d9..3880d1b 100644
--- a/tests/site_geo_dao_redis_impl.test.js
+++ b/tests/site_geo_dao_redis_impl.test.js
@@ -272,7 +272,7 @@ test(`${testSuiteName}: findByGeo no results`, async () => {
 });
 
 // This test is for Challenge #5.
-test.skip(`${testSuiteName}: findByGeoWithExcessCapacity`, async () => {
+test(`${testSuiteName}: findByGeoWithExcessCapacity`, async () => {
   const site1 = {
     id: 1,
     capacity: 4.5,
diff --git a/tests/sliding_ratelimiter_dao_redis_impl.test.js b/tests/sliding_ratelimiter_dao_redis_impl.test.js
index 1b156fe..5c987cb 100644
--- a/tests/sliding_ratelimiter_dao_redis_impl.test.js
+++ b/tests/sliding_ratelimiter_dao_redis_impl.test.js
@@ -52,7 +52,7 @@ const runSlidingWindowTests = async (name, limiterOpts, howMany) => {
 };
 
 // Challenge 7. Remove '.skip' to enable test.
-test.skip(`${testSuiteName}: hit (sliding window limit not exceeded)`, async () => {
+test(`${testSuiteName}: hit (sliding window limit not exceeded)`, async () => {
   const results = await runSlidingWindowTests('testresource', {
     interval: 10000,
     maxHits: 5,
@@ -62,7 +62,7 @@ test.skip(`${testSuiteName}: hit (sliding window limit not exceeded)`, async ()
 });
 
 // Challenge 7. Remove '.skip' to enable test.
-test.skip(`${testSuiteName}: hit (sliding window limit exceeded)`, async () => {
+test(`${testSuiteName}: hit (sliding window limit exceeded)`, async () => {
   let results = await runSlidingWindowTests('testresource2', {
     interval: 10000,
     maxHits: 5,
@@ -79,7 +79,7 @@ test.skip(`${testSuiteName}: hit (sliding window limit exceeded)`, async () => {
 });
 
 // Challenge 7. Remove '.skip' to enable test.
-test.skip(`${testSuiteName}: hit (sliding window ensure window slides)`, async () => {
+test(`${testSuiteName}: hit (sliding window ensure window slides)`, async () => {
   const sliderName = 'testresource4';
   const sliderOpts = {
     interval: 2000,