After the Big Bang occurred, scientists think that the universe. A) Started to expand.

B) Grew less dense.

C) Began to cool.

D) All of these.

Tides are caused by a differences in the gravitational force of the sun at different points on earth. differences in the gravitational force of the moon at different points on earth differences in earth’s gravitational field strength at different points on earth’s surfac fluctuations in the gravitational attraction between earth and the moon.