To do work, this truck uses energy stored in chemical fuel and an electrical battery. How much total energy does this truck put out?

The total energy used to move the truck is

(the amount of energy from burning gasoline)

plus

(the amount of energy taken out of the battery).

(We don't know how much either of those is.)

800 J

Explanation:

To do work, this truck uses energy stored in chemical fuel and an electrical battery.

How much total energy does this truck put out?

50 J

250 J

400 J

800 J

Because all you have to do to find initial energy is add up all the energy that was was used up in different forms.

Kinetic Energy 400 J

Heat Energy 250 J

Friction Energy 150 J

Total Initial Energy 800 J