The ball at 120 meters (m) falls for 20 seconds at a speed of 4 meters (m) per second. Find how many meters (m) the ball is from the ground.
120 4 20 [OP_MUL] [OP_SUB]
var_a = 120
var_b = 4
var_c = 20
var_d = var_b * var_c
var_e = var_a - var_d
print(int(var_e))