2. Carbon dioxide levels in the atmosphere are increased by all of the following except a. Cellular respiration by animals
b. Cellular respiration by plants
c. Photosynthesis by autotrophic organisms d. Combustion of fossil fuels

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.