A quiet moment during a test is interrupted as a physics book falls from a table and strikes the floor. The reaction force to the force of the Earth pulling the book
downwards is
O the book hits the floor
O the floor pushes up on the book
O the book exerts an upward pull on the Earth
O the force of gravity on the book

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.

the answer for apex is the lowest

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.

gravitational energy

electrical energy

kinetic energy

ligh energy