TASK 11A

import tkinter as tk

# Function to change font style

def change_font():

    label.config(font=("Arial", 18, "bold"))

# Create main window

root = tk.Tk()

# Create label with desired text

label = tk.Label(root, text="Hello, World!", font=("Helvetica", 14))

# Add label to main window

label.pack()

# Create button to change font style

button = tk.Button(root, text="Change Font", command=change_font)

# Add button to main window

button.pack()

# Start the main loop

root.mainloop()

TASK 11B

import tkinter as tk

def add():

    try:

        result = float(num1_entry.get()) + float(num2_entry.get())

        result_label.config(text=f"Result: {result}")

    except ValueError:

        result_label.config(text="Please enter valid numbers!")

def subtract():

    try:

        result = float(num1_entry.get()) - float(num2_entry.get())

        result_label.config(text=f"Result: {result}")

    except ValueError:

        result_label.config(text="Please enter valid numbers!")

def multiply():

    try:

        result = float(num1_entry.get()) * float(num2_entry.get())

        result_label.config(text=f"Result: {result}")

    except ValueError:

        result_label.config(text="Please enter valid numbers!")

def divide():

    try:

        num1 = float(num1_entry.get())

        num2 = float(num2_entry.get())

        if num2 == 0:

            result_label.config(text="Cannot divide by zero!")

        else:

            result = num1 / num2

            result_label.config(text=f"Result: {result:.2f}")

    except ValueError:

        result_label.config(text="Please enter valid numbers!")

# Create main window

root = tk.Tk()

root.title("Basic Calculator")

# Input fields

tk.Label(root, text="Enter first number:").pack()

num1_entry = tk.Entry(root)

num1_entry.pack()

tk.Label(root, text="Enter second number:").pack()

num2_entry = tk.Entry(root)

num2_entry.pack()

# Operation buttons

tk.Button(root, text="Add (+)", bg="lightgreen", command=add).pack(pady=2)

tk.Button(root, text="Subtract (-)", bg="lightblue", command=subtract).pack(pady=2)

tk.Button(root, text="Multiply (×)", bg="orange", command=multiply).pack(pady=2)

tk.Button(root, text="Divide (÷)", bg="pink", command=divide).pack(pady=2)

# Result label

result_label = tk.Label(root, text="", font=("Arial", 12, "bold"))

result_label.pack(pady=10)

root.mainloop()