Physics - A 1500 kg car accelerates at 3 m/s/s with an applied force from its engine of 8000 N. What is the force of friction acting on the car?

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

Light from the sun reaches the earth in 8.3 minutes. the velocity is 3.00 x 10^8 m/s. how far is earth from the sun? i know how to get to d = (3 x 10^8 m/s)(498 sec). i just don't know how to get from there to the answer being 1.5 x 10^11 m.

Hydrogen and helium are both members of?