Write pseudocode, draw a flowchart, and develop it on Flowgorithim. for each of the following programs:

1. A program that takes the radius of a circle as input and calculates the area. Formula: Area = π * radius²
2. A program that takes an integer as input and determines whether the number is even or odd.
3. A program that takes three integers as input and finds the largest among them.

4. A program that takes a student's marks in five subjects as input and calculates the average. Based on the average, assign a grade as follows:

   • Average >= 90: Grade A
   • Average >= 80: Grade B
   • Average >= 70: Grade C
   • Average >= 60: Grade D
   • Below 60: Grade F