Answer:
1. 2x
2. v(t) =2
3. 24mph
Step-by-step explanation:
1. W(t) = x^2 -3
dw/dt = 2x dx/dt
2. v(t) =2
Take the derivative to get the acceleration
dv/dt = 0
The choice you picked has 0 velocity so it is not in motion
3. To find the velocity
x(7) - x(5)
---------------
7-5
2(7)^2 -2(5)^2
-----------------
7-5
2*49 - 2*25
---------------2
98-50
---------
2
48/2
24 mph