Day 4 Task
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1.What is meant by Control Statements
2.What is Mean by if else?
3.What are the operators in Control Statements?
4.What is meant by if ladder?
5.How the AND operator will perform?
6.Difference Between AND & OR operator?
7.Difference between if else and nested if?


Questions(Practical):
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Question1:
1.Write a program to input a student's marks and print their grade using the following conditions:
Marks >= 90: Grade A
Marks >= 75: Grade B
Marks >= 50: Grade C
Marks < 50: Fail

Question2:
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2.Write a program to check whether a given year is a leap year or not:
A year is a leap year if it is divisible by 4 but not by 100, unless it is also divisible by 400.
Question3:
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3.Write a program that takes an integer as input and prints whether the number is positive, negative, or zero
Question4:
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4.Write a program to check whether three sides can form a valid triangle:
A triangle is valid if the sum of any two sides is greater than the third side.
Question5:
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5.Write a program that takes a number as input and checks if it is:
Less than 10
Between 10 and 50 (inclusive)
Greater than 50

Questions6:
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6.Write a program to check if a given number is divisible by both 3 and 7.

Question 7
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7.Write a program to calculate the electricity bill based on the following rates:
For the first 100 units: ₹5 per unit
For the next 200 units: ₹7 per unit
Above 300 units: ₹10 per unit
Question 8:
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8.Write a program to implement a basic calculator using if-else for operations:
Addition, subtraction, multiplication, and division.
Take the operation as input from the user.
Input: 
Enter first number: 10
Enter second number: 5
Enter operation (+, -, *, /): *
Output: Result = 50
Question 9:
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Description: Write Python program to allow the user to input his/her age.     
             Then the program will show if the person is eligible to vote.
             A person who is eligible to vote must be older than or equal 1 to 18 years old.
Example:
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Input  = 10
Output = print not eligible.