What happens when you change the material through which a wave travels?

In the diagram below, the northern hemisphere would be in what season at position a a.fall b. winter c.summer d.spring

Which of the following types of reactions would decrease the entropy within a cell? a. dehydration reaction, b. hydrolysis, c. respiration, d. digestion, e. catabolism.

Which pair of sentences is describing the same velocity? a. a car is parked. a car is moving in circles. b. a bus drives 40 miles per hour north. a truck drives 50 miles per hour north. c. a boy walks east at 6 kilometers per hour. a girl walks west at the same speed as the boy. d. valerie rides her bike south at 8 kilometers per hour. owen jogs south at 8 kilometers per hour.