Which one of the following molecules is a by-product of cellular respiration? a. glucose b. water* c. oxygen d. pyruvate

Hurry which of these is true about index fossils? a) are very scarcely found b) used as guides in relative dating c) found in the youngest layer of the rock d) used as reference points in absolute dating

Which of the follow describes a disadvantage secondary sources have compared to primary sources?

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