diff --git a/index.js b/index.js
index 2bb3c16..7f1b7c1 100644
--- a/index.js
+++ b/index.js
@@ -13,7 +13,9 @@ const exampleSongData = require("./data/songs");
  * @param {Object[]} songs - An array of songs.
  * @returns {string[]} Sorted song titles.
  */
-function getSortedTitles(songs) {}
+function getSortedTitles(songs) {
+  return songs.map(songs => songs.title).sort()
+}
 
 // #2
 /**
@@ -22,7 +24,9 @@ function getSortedTitles(songs) {}
  * @param {string} albumName - Name of the album.
  * @returns {string[]} An array of song titles.
  */
-function getSongsFromAlbum(songs, albumName) {}
+function getSongsFromAlbum(songs, albumName) {
+  return songs.filter(song => song.album === albumName).map(song => song.title);
+}
 
 // #3 
 /**
@@ -30,7 +34,13 @@ function getSongsFromAlbum(songs, albumName) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {Object} An object with counts of short, medium, and long songs.
  */
-function categorizeSongsByRuntime(songs) {}
+function categorizeSongsByRuntime(songs) {
+  return {
+    longSongs: songs.filter(song => song.runtimeInSeconds > 300).length,
+    mediumSongs: songs.filter(song => song.runtimeInSeconds >= 180 && song.runtimeInSeconds < 300).length,
+    shortSongs: songs.filter(song => song.runtimeInSeconds < 180).length,
+  }
+}
 
 // #4
 /**
@@ -38,8 +48,28 @@ function categorizeSongsByRuntime(songs) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {string} The name of the album with the most songs.
  */
-function findAlbumWithMostSongs(songs) {}
-
+function findAlbumWithMostSongs(songs) {
+  let albumSongs = {};
+  songs.map(song => {
+    if(!albumSongs.hasOwnProperty(song.album)){
+    albumSongs[song.album]= 1;
+  }
+  else{
+    albumSongs[song.album]++ 
+  }
+}
+  )
+  let songCount = 0;
+  let longestAlbum = "";
+for (let key in albumSongs){
+if(albumSongs[key] > songCount){
+  songCount = albumSongs[key];
+  longestAlbum = key;
+}
+}
+return longestAlbum ;
+}
+findAlbumWithMostSongs(exampleSongData)
 // #5
 /**
  * Returns details of the first song in a specific album.
@@ -47,7 +77,9 @@ function findAlbumWithMostSongs(songs) {}
  * @param {string} albumName - Name of the album.
  * @returns {Object|null} First song object in the album or null.
  */
-function getFirstSongInAlbum(songs, albumName) {}
+function getFirstSongInAlbum(songs, albumName) {
+  return songs.find(song => song.album === albumName);
+}
 
 // #6
 /**
@@ -56,7 +88,15 @@ function getFirstSongInAlbum(songs, albumName) {}
  * @param {number} runtime - The runtime to check against in seconds.
  * @returns {boolean} True if there is at least one song longer than the runtime.
  */
-function isThereLongSong(songs, runtime) {}
+function isThereLongSong(songs, runtime) {
+ if(songs.find(song => song.runtimeInSeconds > runtime)){
+   return true;
+ }
+ else{
+  return false;
+ }
+
+}
 
 // #7
 /**
@@ -64,7 +104,12 @@ function isThereLongSong(songs, runtime) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {Object[]} Array of song objects with runtime in minutes.
  */
-function getSongsWithDurationInMinutes(songs) {}
+function getSongsWithDurationInMinutes(songs) {
+ let runtimeArr = [];
+ songs.forEach(song => runtimeArr.push({title : song.title , durationInMinutes : song.runtimeInSeconds / 60
+}));
+return runtimeArr;
+}
 
 // #8
 /**
@@ -72,7 +117,16 @@ function getSongsWithDurationInMinutes(songs) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {string[]} Array of album names in reverse alphabetical order.
  */
-function getAlbumsInReverseOrder(songs) {}
+function getAlbumsInReverseOrder(songs) {
+  let albumsOrdered = [];
+  songs.forEach(song => {
+    if(!albumsOrdered.includes(song.album)){
+    albumsOrdered.push(song.album)
+  }
+})
+
+  return albumsOrdered.sort((a, b) => a > b ? -1 : a < b ? 1 : 0);
+}
 
 // #9
 /**
@@ -81,7 +135,9 @@ function getAlbumsInReverseOrder(songs) {}
  * @param {string} word - The word to search for in song titles.
  * @returns {string[]} An array of song titles containing the word.
  */
-function songsWithWord(songs, word) {}
+function songsWithWord(songs, word) {
+ return songs.filter(song => song.title.includes(word)).map(song => song.title);
+}
 
 // #10
 /**
@@ -90,29 +146,56 @@ function songsWithWord(songs, word) {}
  * @param {string} artistName - Name of the artist.
  * @returns {number} Total runtime in seconds.
  */
-function getTotalRuntimeOfArtist(songs, artistName) {}
+function getTotalRuntimeOfArtist(songs, artistName) {
+  let totalRuntime = 0
+  songs.filter(song => song.artist === artistName).forEach(song => totalRuntime += song.runtimeInSeconds);
+  return totalRuntime;
+}
 
 // Problem #11
 /**
  * Prints artists who have more than one song in the list.
  * @param {Object[]} songs - An array of songs.
  */
-function printArtistsWithMultipleSongs(songs) {}
+function printArtistsWithMultipleSongs(songs) {
+  let artists = [];
+  songs.forEach(song => artists.includes(song.artist) ? console.log(song.artist) : artists.push(song.artist))
+}
 
 // Problem #12
 /**
  * Logs the longest song title.
  * @param {Object[]} songs - An array of songs.
  */
-function printLongestSongTitle(songs) {}
-
+function printLongestSongTitle(songs) {
+  let titlesArr = songs.sort((a, b) => a.title.length - b.title.length);
+  console.log(titlesArr[titlesArr.length-1].title) ;
+}
+printLongestSongTitle(exampleSongData);
 // Problem #13
 /**
  * Sorts songs by artist name, then by song title alphabetically.
  * @param {Object[]} songs - An array of songs.
  * @returns {Object[]} Sorted array of songs.
  */
-function sortSongsByArtistAndTitle(songs) {}
+function sortSongsByArtistAndTitle(songs) {
+return songs.sort((a, b) => {
+  if(a.artist.toUpperCase() == b.artist.toUpperCase()){
+    if(a.title.toLowerCase() < b.title.toLowerCase()){
+      return -1;
+    }else if(a.title.toLowerCase() > a.title.toLowerCase()){
+      return 1;
+    }
+  }else{
+    if(a.artist.toUpperCase() < b.artist.toUpperCase()){
+      return -1;
+    } else if(a.artist.toUpperCase() > b.artist.toUpperCase()){
+      return 1;
+    }
+    
+  }
+})
+}
 
 // Problem #14
 /**
@@ -120,7 +203,11 @@ function sortSongsByArtistAndTitle(songs) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {Object} An object mapping each album to its total runtime.
  */
-function listAlbumTotalRuntimes(songs) {}
+function listAlbumTotalRuntimes(songs) {
+  const albumRuntimes = {};
+  songs.forEach(song => !albumRuntimes[song.album] ? albumRuntimes[song.album] = song.runtimeInSeconds : albumRuntimes[song.album] += song.runtimeInSeconds);
+  return albumRuntimes;
+}
 
 // Problem #15
 /**
@@ -129,7 +216,9 @@ function listAlbumTotalRuntimes(songs) {}
  * @param {string} letter - The letter to search for.
  * @returns {Object|null} The first song object that matches the criterion or null.
  */
-function findFirstSongStartingWith(songs, letter) {}
+function findFirstSongStartingWith(songs, letter) {
+  return songs.find(song => song.title[0] === letter) || null;
+}
 
 // Problem #16
 /**
@@ -137,7 +226,11 @@ function findFirstSongStartingWith(songs, letter) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {Object} An object mapping each artist to an array of their song titles.
  */
-function mapArtistsToSongs(songs) {}
+function mapArtistsToSongs(songs) {
+  const artistsSongs = {}
+  songs.forEach(song => !artistsSongs[song.artist] ? artistsSongs[song.artist] = [song.title] : artistsSongs[song.artist].push(song.title));
+  return artistsSongs;
+}
 
 // Problem #17
 /**
@@ -145,29 +238,90 @@ function mapArtistsToSongs(songs) {}
  * @param {Object[]} songs - An array of songs.
  * @returns {string} The name of the album with the longest average song runtime.
  */
-function findAlbumWithLongestAverageRuntime(songs) {}
+function findAlbumWithLongestAverageRuntime(songs) {
+  let highestAverageRuntime = 0;
+  let highestAverageAlbum = "";
+  let countAndTime = {};
+  songs.forEach(song => {
+    if(!countAndTime[song.album]){
+      countAndTime[song.album] = {
+        runtime : song.runtimeInSeconds,
+        songCount : 1
+      }
+    }
+    else {
+      countAndTime[song.album].runtime += song.runtimeInSeconds;
+      countAndTime[song.album].songCount++;
+    }
+  })
+  for(const album in countAndTime){
+    if(countAndTime[album].runtime / countAndTime[album].songCount > highestAverageRuntime){
+      highestAverageAlbum = album;
+      highestAverageRuntime = countAndTime[album].runtime / countAndTime[album].songCount;
+    }
+  }
+  return highestAverageAlbum;
+}
 
 // Problem #18
 /**
  * Logs song titles sorted by their runtime.
  * @param {Object[]} songs - An array of songs.
  */
-function printSongsSortedByRuntime(songs) {}
+function printSongsSortedByRuntime(songs) {
+songs.sort((a, b) => a.runtime - b.runtime);
+return songs.forEach(song => console.log(song.title));
+}
 
 // Problem #19
 /**
  * Prints a summary of each album, including its name, total runtime, and number of songs.
  * @param {Object[]} songs - An array of songs.
  */
-function printAlbumSummaries(songs) {}
-
+function printAlbumSummaries(songs) {
+  let albumSummaries = {};
+  songs.forEach(song => {
+    if(!albumSummaries[song.album]){
+      albumSummaries[song.album] = {name : song.album,
+                                    totalRuntime : song.runtimeInSeconds,
+                                    songCount : 1}
+    }
+    else{
+      albumSummaries[song.album].totalRuntime += song.runtimeInSeconds;
+      albumSummaries[song.album].songCount++;
+    }
+  })
+  for (let albumKey in albumSummaries){
+    console.log(`${albumSummaries[albumKey].name}: ${albumSummaries[albumKey].songCount} songs, Total Runtime: ${albumSummaries[albumKey].totalRuntime} seconds`)
+}
+}
+printAlbumSummaries(exampleSongData);
 // Problem #20
 /**
  * Finds the artist with the most songs in the list.
  * @param {Object[]} songs - An array of songs.
  * @returns {string} The name of the artist with the most songs.
  */
-function findArtistWithMostSongs(songs) {}
+function findArtistWithMostSongs(songs) {
+  let artistSongCounts = {};
+  songs.forEach(song => {
+    if (!artistSongCounts[song.artist]){
+      artistSongCounts[song.artist] = 1
+    }
+    else{
+      artistSongCounts[song.artist] ++
+    }
+  })
+  let artistWithMostSongs = "";
+  let highestSongCount = 0;
+  for(let artist in artistSongCounts){
+    if(artistSongCounts[artist] > highestSongCount){
+      artistWithMostSongs = artist;
+      highestSongCount = artistSongCounts[artist];
+    }
+  }
+  return artistWithMostSongs;
+}
 
 
 module.exports = {