Which scientific theory explains that the universe originated from a small densely packed space

Clyde and marilyn are riding a roller coaster. during which section(s) of the track is their potential energy converted to kinetic energy? a. from point b to point c only b. from point b to point d only c. from point a to point b only d. from point a to point b and from point c to point d

Which substance has non polar covalent bonds

Reactions in cells take place at about a. 40°c b. 0° c. 100°c d. 60°c