Ariana is accelerating her car at 4.6 m/s2 it took her 10 seconds to reach this acceleration her starting velocity was om/s what was her final velocity

Acceleration of the car = 4.6 m/s^2
Initial time taken (T1)  = 0 second
Final time taken (T2) = 10 seconds
Initial velocity of the car (V1) = 0 m/s
Let us assume the final velocity of the car (V2) = x m/s
Then
Acceleration of the car = (V2 - V1)/(T2 - T1)
4.6 = (x - 0)/(10 - 0)
4.6 = x/10
x = 4.6 * 10
  = 46 m/s
So the final velocity of the car Ariana is driving is 46 m/s.I hope the procedure is clear enough for you to understand. In future you can always use this procedure for solving similar problems without requiring any help from outside.

Efficiency is an action of doing something. for example when you take a test. good efficiency means you did well but bad effeciency or no effiency means you did bad.

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