I think the answer is c AC power source
Hope this help you?
If you were to sit a hot cup of water out side it would frezze faster
Answer: -3.49 m/s (to the south)
Explanation:
This problem can be solved by the Conservation of Momentum principle which establishes the initial momentum 
must be equal to the final momentum 
, and taking into account this is aninelastic collision:
Before the collision:
(1)
After the collision:
(2)
Where:
is the mass of the car
is the velocity of the car, directed to the north
is the mass of the truck
is the velocity of the truck, directed to the south
is the final velocity of both the car and the truck
(3)
(4)
Isolating :
(5)
(6)
Finally:
The negative sign indicates the direction of the velocity is to the south
Impulse is a force acting briefly on a body and producing a finite change of momentum.
This relates to momentum because impulse is a change in momentum. Impulse = momentum. Since force is a vector quantity, impulse is also a vector in the same direction. Impulse applied to an object produces equivalent vector change in its linear momentum, also in the same direction. m•(triangle)v
