12 ln muscle constriction; a) Chemical energy transforms directly into thermal energy and than into mechanical work. b) Chemical energy transforms directly into mechanical energy (work);
c) Chemical energy transforme directly into electric energy and than into mechanical work.
d) Chemical energy transform directly into thermal and electric energy and than into mechanical work.

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.

a skateboard rolling across the street - apex