*15-8. The 1.5-Mg four-wheel-drive jeep is used to push two identical crates, each having a mass of 500 kg. If the coefficient of static friction between the tires and the ground is µ, = 0.6, determine the maximum possible speed the jeep can achieve in 5 s without causing the tires to slip.The coefficient of kinetic friction between the crates and the ground is µ̟ = 0.3.