3a

[legend17-dot]

import math
n = int(input("Enter the number of elements: "))
numbers = [ ]
for i in range(n):
num = float(input("Enter number: "))
numbers.append(num)

Mean

mean = sum(numbers) / n

Variance

variance = 0
for x in numbers:
variance = variance + (x - mean) ** 2
variance = variance / n

Standard Deviation

std_dev = math.sqrt(variance)
print("Numbers in the list:", numbers)
print("Mean =", mean)
print("Variance =", variance)
print("Standard Deviation =", std_dev)