15 ! (show all your work) problem: antti entered a 10-kilometer race. his goal is to finish in one hour. he starts off sprinting, and completes the first 2 kilometers of the race at an average speed of 12 kilometers per hour. to achieve his goal of a one-hour finish time, what average speed must antti maintain for the last 8 kilometers of the race? enter your answer as a number in decimal form, without units.