Acar advertisement states that a certain car that emily miller loves can accelerate from rest to 70 km/h in 7 seconds. find the cars average acceleration

Kinematics equations are vital for this:

v_0(initial velocity)           v_f(final velocity)     a(acceleration)

v_0=70 km/h    v_f= 0 km/h( rest)

Kinematics equation is a=(v_f-v-0)/time
a=(0-70)/(7/3600)  which means it decelerates at -36000 km/h

This number is humongous; I would advise you to re-check the problem and see if the the time it takes is 7 hours rather than 7 seconds. Notice that I put the time as 7/3600 because it is 7 seconds which should be converted to hours.