#!/usr/bin/env python

from math import pi

def volume_sphere(rayon):
    return (4/3)*pi*rayon**3

def prix_livre(nbr, prix):
    return ((prix*nbr) - (prix*nbr*(40/100)) + (3 + 0.75*(prix - 1)))

def time_per_miles(km, h, m, s):
    mi = km / 1.61 # km to mi
    total_sec = h *60 + m * 60 + s
    return mi / total_sec

def time_per_miles(km, h, m, s):
    mi = km / 1.61 # km to mi
    total_sec = h *60 + m * 60 + s
    return mi / total_sec

def mi_per_h(km, h, m, s):
    mi = km / 1.61
    total_h = h + m / 60 + s /3600
    return mi / total_h

if __name__ == "__main__":
    vol = volume_sphere(5)
    print(vol)

    nbre_livre = prix_livre(60, 24.95)
    print(nbre_livre)

    time = time_per_miles(10, 0, 43, 30)
    print(time)

    speed = mi_per_h(10, 0, 43, 30)
    print(speed)