Acar traveling at 21 m/s starts to decelerate steadily. it comes to a complete stop in 8 seconds. what is its acceleration?

i have to put in the answer and the unit

Ifeel like lily and ledbetter had a fair pay act just because it was necessary especially at those times

2. they have negligible mass.

If there was no gravity then their would be no downword force on the football to have it return the the grownd, and if there was no friction (mainly air friction) then there would be no opposing force the stop the ball from moving through the air allowing the ball to travle ∞.

    5.5 n======    assuming that      we have      m = 0.145 kg    a = 38 m/s²therefore    5.51 n, but two significant figures.final answer: 5.5 n