diff --git a/Sprint-2/debug/address.js b/Sprint-2/debug/address.js
index 940a6af8..ffb1f485 100644
--- a/Sprint-2/debug/address.js
+++ b/Sprint-2/debug/address.js
@@ -1,4 +1,4 @@
-// Predict and explain first...
+// Predict and explain first... - I don't see the return, I think it's a problem. I would change [0] to (houseNumber), it's will show undefined error
 
 // This code should log out the houseNumber from the address object
 // but it isn't working...
@@ -10,6 +10,14 @@ const address = {
   city: "Manchester",
   country: "England",
   postcode: "XYZ 123",
+
 };
 
-console.log(`My house number is ${address[0]}`);
+console.log(`My house number is ${address[0]}`); // - address is an object, not an array. So JavaScript doesn't know what address[0] is — it'll return undefined.
+console.log(`My house number is ${address["houseNumber"]}`);
+
+console.log(`My city is ${address["city"]}`);
+//or
+console.log(`My city is ${address.city}`);
+
+//I had mistake in my prediction, it does't need return because it's not a function. 
diff --git a/Sprint-2/debug/author.js b/Sprint-2/debug/author.js
index 8c212597..6c863256 100644
--- a/Sprint-2/debug/author.js
+++ b/Sprint-2/debug/author.js
@@ -1,7 +1,7 @@
-// Predict and explain first...
+// Predict and explain first... It's will be undefined. I will create separate const value and just after made console.log (value). 
 
 // This program attempts to log out all the property values in the object.
-// But it isn't working. Explain why first and then fix the problem
+// But it isn't working. Explain why first and then fix the problem - it's showing typeError. I think it's because 'for' as I know it's for loop in arrays but I don't see any loop there. 
 
 const author = {
   firstName: "Zadie",
@@ -11,6 +11,15 @@ const author = {
   alive: true,
 };
 
-for (const value of author) {
+// for (const value of author) {
+//  console.log(value);
+// }
+
+for (const value of Object.values(author)) {
   console.log(value);
 }
+
+// const value = author
+// console.log(value);
+
+
diff --git a/Sprint-2/debug/recipe.js b/Sprint-2/debug/recipe.js
index 6cbdd22c..87b571d0 100644
--- a/Sprint-2/debug/recipe.js
+++ b/Sprint-2/debug/recipe.js
@@ -1,8 +1,8 @@
-// Predict and explain first...
+// Predict and explain first...- I think it's will find 'title' and 'serves' but will not find 'ingredients', ingredients will be undefined. 
 
 // This program should log out the title, how many it serves and the ingredients.
-// Each ingredient should be logged on a new line
-// How can you fix it?
+// Each ingredient should be logged on a new line 
+// How can you fix it? - I will write console.log for each ingredient's separate , so it's will be in the new line
 
 const recipe = {
   title: "bruschetta",
@@ -10,6 +10,33 @@ const recipe = {
   ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
 };
 
+// console.log(`${recipe.title} serves ${recipe.serves}
+//   ingredients:
+// ${recipe}`);
+
+////
+
 console.log(`${recipe.title} serves ${recipe.serves}
-  ingredients:
-${recipe}`);
+ingredients: 
+  ${recipe.ingredients[0]}
+  ${recipe.ingredients[1]}
+  ${recipe.ingredients[2]}
+  ${recipe.ingredients[3]
+  }`);
+
+  //or
+
+  console.log(recipe.title);
+console.log(`Serves: ${recipe.serves}`);
+console.log("Ingredients:");
+for (const ingredient of recipe.ingredients) {
+  console.log(ingredient);
+}
+
+//or
+
+console.log(`${recipe.title} serves ${recipe.serves}`);
+console.log(recipe.ingredients[0]);
+console.log(recipe.ingredients[1]);
+console.log(recipe.ingredients[2]);
+console.log(recipe.ingredients[3]);
\ No newline at end of file
diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index cd779308..15689eff 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,3 +1,18 @@
-function contains() {}
+function contains(obj, property) {
+      
+        if (typeof obj !== "object" || obj === null || Array.isArray(obj)) {
+        return false; 
+    }
+      
+        return property in obj; 
+      }
+
+console.log(contains({ a: 1, b: 2 }, "a")); // true
+console.log(contains({ a: 1, b: 2 }, "c")); // false
+console.log(contains({}, "a")); // false
+console.log(contains(null, "a")); // false
+console.log(contains([], "length")); // false 
+console.log(contains(42, "a")); // false 
+console.log(contains("string", "length")); // false 
 
 module.exports = contains;
diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 326bdb1f..a02f7d67 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -33,3 +33,27 @@ test.todo("contains on empty object returns false");
 // Given invalid parameters like an array
 // When passed to contains
 // Then it should return false or throw an error
+
+
+describe("contains function", () => {
+
+    // Test 1: Given an empty object, should return false
+    test("contains on empty object returns false", () => {
+      expect(contains({}, 'a')).toBe(false);
+    });
+  
+    // Test 2: Given an object with properties, should return true for an existing property
+    test("contains with existing property returns true", () => {
+      expect(contains({ a: 1, b: 2 }, 'a')).toBe(true);
+      expect(contains({ a: 1, b: 2 }, 'b')).toBe(true);
+    });
+  
+    // Test 3: Given an object with properties, should return false for a non-existent property
+    test("contains with non-existent property returns false", () => {
+      expect(contains({ a: 1, b: 2 }, 'c')).toBe(false);
+      expect(contains({ a: 1, b: 2 }, 'z')).toBe(false);
+    });
+  
+
+  
+  });
diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index a6746e07..20f5d668 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,5 +1,18 @@
-function createLookup() {
-  // implementation here
+
+
+function createLookup(array) {
+  let object = {}
+  for (const list of array) {
+    console.log(list);
+    object[list[0]] = list[1]
+  } 
+  console.log (object)
+  return object
+
 }
 
+//const countryCurrencyPairs = [['US', 'USD'], ['CA', 'CAD'], ['UA', 'GRN']]
+//createLookup(countryCurrencyPairs) 
+
+
 module.exports = createLookup;
diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 547e06c5..daa522ef 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -32,4 +32,16 @@ It should return:
    'US': 'USD',
    'CA': 'CAD'
  }
-*/
+*/ 
+//const countryCurrencyPairs = [['US', 'USD'], ['CA', 'CAD']]
+//createLookup(countryCurrencyPairs) 
+
+describe("lookup", () => {
+  test("should return object in muly courency", () => {
+    expect(createLookup([['US', 'USD'], ['CA', 'CAD']])).toEqual({
+      'US': 'USD',
+      'CA': 'CAD'
+    });
+  });
+})
+
diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 45ec4e5f..26dba25e 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -6,11 +6,19 @@ function parseQueryString(queryString) {
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
+    const [key, value] = pair.split(/=(.*)/);
     queryParams[key] = value;
   }
 
   return queryParams;
 }
+parseQueryString("equation=x=y+1")
+
+// Object {
+//   -   "equation": "x=y+1", - ожидаем
+//   +   "equation": "x", - то что мы получили
+
+//"equation=x=y+1" - передали
+// equation": "x=y+1 - ожидаем получить
 
 module.exports = parseQueryString;
diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 3e218b78..eb9b6a5f 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -10,3 +10,4 @@ test("parses querystring values containing =", () => {
     "equation": "x=y+1",
   });
 });
+
diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index f4732181..5387e074 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,3 +1,25 @@
-function tally() {}
+    function tally(items) {
+        
+        if (!Array.isArray(items)) {
+          throw new Error("Input must be an array");
+        }
+    
+        const counts = {};
+        items.forEach(element => {
+          if (counts[element]) {
+            counts[element]++;
+          } else {
+            counts[element] = 1;
+          }
+        });
+        return counts;
+      }
+      
+      console.log(tally(['a']));  // { a: 1 }
+      console.log(tally(['a', 'a', 'a']));  // { a: 3 }
+      console.log(tally(['a', 'a', 'b', 'c']));  // { a: 2, b: 1, c: 1 }
+      console.log(tally([]));  // {}
+
+
 
 module.exports = tally;
diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index bb353fb1..a6f50723 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -10,20 +10,26 @@ function invert(obj) {
   const invertedObj = {};
 
   for (const [key, value] of Object.entries(obj)) {
-    invertedObj.key = value;
+    invertedObj [value] = key;
   }
-
   return invertedObj;
 }
 
-// a) What is the current return value when invert is called with { a : 1 }
 
+// a) What is the current return value when invert is called with { a : 1 }
+console.log(invert({ a: 1 }));         // Expected: { "1": "a" }
 // b) What is the current return value when invert is called with { a: 1, b: 2 }
-
+console.log(invert({ a: 1, b: 2 }));   // Expected: { "1": "a", "2": "b" }
 // c) What is the target return value when invert is called with {a : 1, b: 2}
 
-// c) What does Object.entries return? Why is it needed in this program?
+// the same with b)
 
 // d) Explain why the current return value is different from the target output
-
+console.log(invert({ x: 10, y: 20 })); // Expected: { "10": "x", "20": "y" }
 // e) Fix the implementation of invert (and write tests to prove it's fixed!)
+
+
+console.log(invert({ a: 1 }));         // Expected: { "1": "a" }
+console.log(invert({ a: 1, b: 2 }));   // Expected: { "1": "a", "2": "b" }
+console.log(invert({ x: 10, y: 20 })); // Expected: { "10": "x", "20": "y" }
+console.log(invert({}));