diff --git a/JavaScript/Tasks/1-angular.mjs b/JavaScript/Tasks/1-angular.mjs
index 6ef9707..b6732db 100644
--- a/JavaScript/Tasks/1-angular.mjs
+++ b/JavaScript/Tasks/1-angular.mjs
@@ -14,13 +14,9 @@ const electronics = [
 
 const items = signal(electronics);
 
-const total = (items) => {
-  let result = 0;
-  for (const item of items) {
-    result += item.price;
-  }
-  return result;
-};
+const total = computed(() => 
+  items().reduce((sum, item) => sum + item.price, 0)
+);
 
-console.log(`Total: ${total(items())}`);
-console.log(computed);
+console.log(`Total: ${total()}`);
+console.log(computed);
\ No newline at end of file
diff --git a/JavaScript/Tasks/2-preact.js b/JavaScript/Tasks/2-preact.js
index f1abd2d..d33e960 100644
--- a/JavaScript/Tasks/2-preact.js
+++ b/JavaScript/Tasks/2-preact.js
@@ -14,13 +14,9 @@ const electronics = [
 
 const items = signal(electronics);
 
-const total = (items) => {
-  let result = 0;
-  for (const item of items) {
-    result += item.price;
-  }
-  return result;
-};
+const total = computed(() =>
+  items.value.reduce((sum, item) => sum + item.price, 0)
+);
 
-console.log(`Total: ${total(items.value)}`);
+console.log(`Total: ${total.value}`);
 console.log(computed);
diff --git a/JavaScript/Tasks/3-effect.js b/JavaScript/Tasks/3-effect.js
index 1ad3f1f..bfc8438 100644
--- a/JavaScript/Tasks/3-effect.js
+++ b/JavaScript/Tasks/3-effect.js
@@ -15,7 +15,36 @@ const electronics = [
 
 const total = signal(0);
 
+const items = signal([...electronics]);
+
 effect(() => {
-  console.log(electronics);
-  console.log({ total });
+  let sum = 0;
+  for (const item of items.value) {
+    sum += item.price;
+  }
+  
+  total.value = sum;
+  
+  console.log('Current state');
+  console.log('Items:', items.value);
+  console.log('Total:', total.value);
 });
+
+console.log('\nInitial state:');
+
+setTimeout(() => {
+  console.log('\nAdding a new item');
+  items.value = [...items.value, { name: 'Mouse', price: 50 }];
+}, 1000);
+
+setTimeout(() => {
+  console.log('\nRemoving an item');
+  items.value = items.value.filter(item => item.name !== 'Keyboard');
+}, 2000);
+
+setTimeout(() => {
+  console.log('\nUpdating item price');
+  items.value = items.value.map(item => 
+    item.name === 'Laptop' ? {...item, price: 1600} : item
+  );
+}, 3000);
\ No newline at end of file
diff --git a/JavaScript/Tasks/4-dispose.js b/JavaScript/Tasks/4-dispose.js
index 8069cf5..aac19e4 100644
--- a/JavaScript/Tasks/4-dispose.js
+++ b/JavaScript/Tasks/4-dispose.js
@@ -18,9 +18,53 @@ const electronics = [
 ];
 
 const total = signal(0);
+const items = signal([...electronics]);
 
-effect(() => {
-  console.log(electronics);
-  console.log({ total });
-  console.log({ PURCHASE_LIMIT });
+let disposeEffect = null;
+
+function addRandomItem() {
+  const randomItems = [
+    { name: 'Mouse', price: 50 },
+    { name: 'Monitor', price: 200 },
+    { name: 'Headphones', price: 80 },
+    { name: 'USB Cable', price: 15 }
+  ];
+  
+  const randomItem = randomItems[Math.floor(Math.random() * randomItems.length)];
+  items.value = [...items.value, randomItem];
+  return randomItem;
+}
+
+disposeEffect = effect(() => {
+  total.value = items.value.reduce((sum, item) => sum + item.price, 0);
+  
+  if (total.value <= PURCHASE_LIMIT) {
+    console.log('Current purchase');
+    console.log('Items:', items.value.map(i => `${i.name}: $${i.price}`).join(', '));
+    console.log(`Total: $${total.value} (Limit: $${PURCHASE_LIMIT})`);
+  }
 });
+
+const interval = setInterval(() => {
+  if (total.value > PURCHASE_LIMIT * 2) {
+    clearInterval(interval);
+    if (disposeEffect) disposeEffect();
+    console.log(`Final total: $${total.value} (Process stopped)`);
+    return;
+  }
+  
+  const newItem = addRandomItem();
+  console.log(`Added: ${newItem.name} for $${newItem.price}`);
+  
+  if (total.value > PURCHASE_LIMIT && disposeEffect) {
+    console.log(`\n Limit exceeded ($${total.value} > $${PURCHASE_LIMIT}), stopping output\n`);
+    disposeEffect();
+    disposeEffect = null;
+  }
+}, 1000);
+
+setTimeout(() => {
+  if (interval) clearInterval(interval);
+  if (disposeEffect) disposeEffect();
+  console.log(`Final total: $${total.value} (Timeout reached)`);
+}, 10000);
\ No newline at end of file
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..aa247d9
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,60 @@
+{
+  "name": "Signals",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "@angular/core": "^20.0.3",
+        "@preact/signals-core": "^1.10.0"
+      }
+    },
+    "node_modules/@angular/core": {
+      "version": "20.0.3",
+      "resolved": "https://registry.npmjs.org/@angular/core/-/core-20.0.3.tgz",
+      "integrity": "sha512-kB6w1bQgClfmkTbWJeD3vSLqX0e3uSaJD6KJ7XXT1IEaqUs4J+mKRKHQyxpJlpdUb7R+jDaHSM/vrVF15/L2rA==",
+      "dependencies": {
+        "tslib": "^2.3.0"
+      },
+      "engines": {
+        "node": "^20.19.0 || ^22.12.0 || >=24.0.0"
+      },
+      "peerDependencies": {
+        "@angular/compiler": "20.0.3",
+        "rxjs": "^6.5.3 || ^7.4.0",
+        "zone.js": "~0.15.0"
+      },
+      "peerDependenciesMeta": {
+        "@angular/compiler": {
+          "optional": true
+        },
+        "zone.js": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/@preact/signals-core": {
+      "version": "1.10.0",
+      "resolved": "https://registry.npmjs.org/@preact/signals-core/-/signals-core-1.10.0.tgz",
+      "integrity": "sha512-qlKeXlfqtlC+sjxCPHt6Sk0/dXBrKZVcPlianqjNc/vW263YBFiP5mRrgKpHoO0q222Thm1TdYQWfCKpbbgvwA==",
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/preact"
+      }
+    },
+    "node_modules/rxjs": {
+      "version": "7.8.2",
+      "resolved": "https://registry.npmjs.org/rxjs/-/rxjs-7.8.2.tgz",
+      "integrity": "sha512-dhKf903U/PQZY6boNNtAGdWbG85WAbjT/1xYoZIC7FAY0yWapOBQVsVrDl58W86//e1VpMNBtRV4MaXfdMySFA==",
+      "peer": true,
+      "dependencies": {
+        "tslib": "^2.1.0"
+      }
+    },
+    "node_modules/tslib": {
+      "version": "2.8.1",
+      "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.8.1.tgz",
+      "integrity": "sha512-oJFu94HQb+KVduSUQL7wnpmqnfmLsOA/nAh6b6EH0wCEoK0/mPeXU6c3wKDV83MkOuHPRHtSXKKU99IBazS/2w=="
+    }
+  }
+}
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..6a9d826
--- /dev/null
+++ b/package.json
@@ -0,0 +1,6 @@
+{
+  "dependencies": {
+    "@angular/core": "^20.0.3",
+    "@preact/signals-core": "^1.10.0"
+  }
+}