physics repost
posted by Jon on .
9)You are taking a road trip to the beach for Spring Break. You leave at 12:00pm. At 12:10 you stop for lunch 10 miles down the road. You get back on the road and travel 75 more miles and realize that you need to stop for gas. You notice that it is now 1:10pm. At this point in the trip, what is your average velocity in miles per hour?
11)A race car travels on a racetrack at 38 m/s and slows at a constant rate to a velocity of 20 m/s over 10 s. How far does it move during this time?
d=Vi(t)+1/2(a)(t^2)
d=38(10)+(1/2)(1.8)(100)
I got 470 meters but my choices are:200,290,380,and 760 so I chose 380

On 9) I will be happy to critique your thinking.
on 11) distance while slowing?
average velocity=29
distance=avgvelocity*time....
On your work, a should be negative.... 
9)I multiplied total distance 85 miles times total time of 70 min. and got 1.21 mi/hr

I divided of course