During the period, close to 90% of all species are thought to have gone extinct.

Always use significant figure rules. remember that these rules apply to all numbers that are measurements. a car travels 6 miles north, 3 miles east, and then 2 miles south. what is the distance traveled? a.7 b.11

Which of these is not an example of molecular homology? 1. use of dna and rna as genetic material 2.use of glycolysis as the first step in cellular respiration in both plants and animals 3. the lack of an igf-1 gene in prokaryotes 4. the use of aldolase b to break down fructose in bacteria, plants and animals

When an object is moving away from you while still making a sound, the pitch of the sound is perceived to a. lower b. unchanged c. fluctuating d.higher