A space vehicle is in a circular orbit at an altitude of 225 mi above the earth. To return to earth, it decreases its speed as it passes through A by firing its engine for a short interval of time in a direction opposite to the direction of its motion. Knowing that the velocity of the space vehicle should form an angle φB = 60o with the vertical as it reaches Point B at an altitude of 40 mi,

Determine

(a) The required speed of the vehicle as it leaves its circular orbit at A,

(b) Its speed at Point B.