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## Homework Statement

I have three questions total (did five already). I don't want the straight-answers but I need help working them through since I want to do them myself. Here's the first one:

---To set a speed record in a measured (straight-line) distance d, a race car must be driven first in one direction (in time t1) and then in the opposite direction (in time t2). (a) To eliminate the effects of the wind and obtain the car's speed vc in a windless situation, what number of method should we use: the average of d/t1 and d/t2 (method 1) or should we divide d by the average of t1 and t2 (method 2)? (b) What is the fractional difference in the two methods when a steady wind blows along the car's route and the ratio of the wind speed vw to the car's speed vc is 0.0440?----

Other question: ----An electric vehicle starts from rest and accelerates at a rate a1 in a straight line until it reaches a speed of v. The vehicle then slows at a constant rate a2 until it stops. (a) How much time elapses from start to stop? (b) How far does the vehicle move from start to stop? Give your answers in terms of the given variables. ---

## Homework Equations

## The Attempt at a Solution

For (a) my guess is method 1. It makes more sense. I don't understand (b), though.