1.Today I drove 125 miles in 110 minutes.What was my` averag

1、Today I drove 125 miles in 110 minutes。What was my` average speed in miles per hour?(There are 60 minutes in one hour)Ans：average speed v=total course/time cost=125/(110/60)≈68。18 miles/hour2、Light travels through space at a constant speed of 3X10⁸m/s。What is the acceleration of a beam of light?Ans：Since the speed of a beam of light is a constant,the acceleration is zero(0)。3、what is the acceleration of a car if it begins at 100km/h and comes to a stop after 8 seconds?you may write your answer with the units of km/h/s。In what direction is the car's acceleration (in the same direction or opposite direction of the car's motion)?Ans:the acceleration a=(0-100)/8=-12。5km/h/swhere "-" suggests that the acceleration is opposite the direction of the car's motion。