a) The Mars Global Surveyor orbits Mars at an average altitude of 405 km. The average radius of Mars is 3390 km. If it takes the spacecraft 1.95 hours to complete one orbit around the planet, what is it's tangential velocity in kilometers per hour?

b) In the activity problem, if the spacecraft's tangential velocity slows down to 10,000 kilometers per hour over a time of 6 minutes, what is the angular acceleration(deceleration) in units of radians per hour squared? Please enter your answer as a positive number with 2 decimal places and no units.