A sprinter explodes out of the starting block with an acceleration of +3.3 m/s^{2}, which she sustains for 1.1 s. Then, her acceleration drops to zero for the rest of the race.

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Think about the two components of her travel distance
1) in cart = +3.3m/s while walking 1.1*t (t=unknown time that we wish to solve)
Then the total distance which can be expressed as the total time(1.1)*ave speed. Equate the two, and solve for t

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