Resistive Force

1. The problem statement, all variables and given/known data
On Land, a 5000kg amphibious vehicle can accelerate from rest to 10 m/s in 25 sec.


Find...
a)Final Kinetic Energy?
-250,000
b)Avg Power furnished by engine during acceleration?
-10,000
c)If the same power is required to propel the vehicle through water at a constant 2 m/s, What is the magnitude of the resistive force being overcome?

The attempt at a solution
I havent learn or dont know what is the meaning of Resistive Force, I tried searching for a formula online but they do not make sense.

 

speed remains the same, it does not increase or decrease

 

instantaneous acceleration?