import math

def calc_area_circle(r):
    return math.pi * r ** 2

def calc_area_rect(w, h):
    return w * h

def calc_area_square(s):
    return calc_area_rect(s, s)

def calc_vol_sphere(r):
    return math.pi * 4 / 3 * r ** 3

def calc_vol_rect(w, h, b):
    return w * h * b