'I am NOT an alcoholic': Gerard Butler reveals the real reason behind his stretch in rehab. Actor Gerard Butler has revealed his rehab agony and set the record straight over rumours of his alcoholism. The 42-year-old Scot checked into the Betty Ford Centre in February for three weeks after being injured in a surfing accident. He said: 'Maybe a stronger person wouldn't have needed to go. But I'm glad I did it.
Gravity is one major force that creates tides. In 1687, Sir Isaac Newton explained that ocean tides result from the gravitational attraction of the sun and moon on the oceans of the earth (Sumich, J.L., 1996).
3 | P a g e Teaching Lesson 10 Lesson 10 b. Semidiurnal tide means a location has two low tides and two high tides each day with the low tides equal in size and the high tides equal in size.