You give a book a brief push to make it slide up a rough inclined surface. It comes to a stop and slides back down to the starting point.
Does it take the same amount of time to go up as it does to come down?

No, it will take a longer time to slide up than to slide down.

Explanation: An inclined plane is a plane that slides at an angle to the ground,this angle can be 45 degrees,60degrees etc. WHEN AN OBJECT IS SLIDING UP A ROUGH INCLINED SURFACE, IT WILL HAVE TO OVERCOME THE FRICTION OR RESISTANCE OF THE ROUGH SURFACE AND THE OPPOSITION OF THE FORCE IF GRAVITY, WHICH WILL CAUSE IT TO TAKE A LONGER TIME TO GO UP WHILE WHEN SLIDING DOWN IT WILL ONLY HAVE TO OVERCOME THE FRICTION OF THE ROUGH SURFACE AS THE FORCE OF GRAVITY ACTS TO PULL IT DOWN THE SLOPE.

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.