A sprinter set a high school record in track and field, running 200.0 m in 20.6 s. what is the average speed of the sprinter in kilometers per hour?

First we will calculate the acceleration in m/s^2 then we just convert:

the formula for the acceleration is a = delta v over delta t where delta v is the final velocity 200m/s less initial velocity 0m/s so delta v is 200m/s and delta t is final velocity 20.6s less initial velocity that always will be 0 then 20.6 - 0 = 20.6 so a = 200 over 20.6 that is approximately 9.7m/s^2 (remember that is squared) now we convert a = 200*0,001 (since 1 meter is 0,001 km) = 0.2 km and now we convert the time that is 20.6s/3600s (since one hour is 3600s) = approximately 0.0057h then 0.2/0.0057 is approximately a acceleration of 34,95km/h^2