What is the ultimate source of most energy on earth ?

Which of the following describes the difference in stimuli required to detect a difference between the stimuli? a. just noticeableb. signal detectionc. subliminald. top down

Methane gas created by a cows flatulence especially in a large herd is a greenhouse gas. true or false.

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.