Guys I am having a problem finishing this code project.I am having trouble in finishing its all 3 test samples. Help me guys

Question

We are going to write a program that will calculate the area of ​​a circle.
The area enclosed by a circle of radius r is πr², where π (pi) is the constant ratio of the circumference of any circle to its diameter, and r is the radius.
The given program declares a constant pi variable with a value of 3.14.
Complete the program to take the radius as input, then calculate and output the area of the circle.

Sample Input
5

Sample Output
78.5

Answer 1

radius =Convert.ToDouble(Console.ReadLine());

Answer 2

thanks

Answer 3

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SoloLearn
{
class Program
{
static void Main(string[] args)
{
const double pi = 3.14;
double radius;
radius =Convert.ToDouble(5);
double area;
area =pi*radius*radius;
Console.WriteLine(area);

//your code goes here

}
}
}

Answer 4

there are test cases using 5 ,6.4,10

Answer 5

ok I'll try that