Answer:
Given: mass 1200kg
initial velocity: 4m/s
finial velocity: 10 m/s
time 3 sec
then
speed; initial velocity + final velocity/2
4+10/3
: 4.66m/s2
1 horsepower is equal to 746 W, so the power of the engine is

The power is also defined as the energy E per unit of time t:

Where the energy corresponds to the work done by the engine, which is

. Re-arranging the formula, we can calculate the time t needed to do this amount of work:
Rocks and sediments I believe
In electrical engineering, ground or earth is the reference point in an electrical circuit from which voltages are measured, a common return path for electric current, or a direct physical connection to the earth. Electrical circuits may be connected to ground (earth) for several reasons.