About how many years ago do scientists suggest that the earth cooled enough for water vapor to condense.

A) 20 millions years

B) 4.6 billion years

C) 4.4 billion years

D) 5.5 billion years

Which culprit originates an allergic response and causes Juan to sneeze when he sniffs the morning glory flower? A) plant toxins B) antihistimines C) plant antibodies D) harmless plant proteins

A test mating of organisms

If plants dont move why do they need energy

In the early 1800s, Darwin studied 13 kinds of finches. What did Darwin hypothesize about these birds? a. The different finches could breed and produce fertile offspring. b. The finches were different species that shared a common ancestor. c.

Some people can get the flu from the flu shot. True or False. and explain.

The energy to power passive transport comes from:

By which process does water vapor become a cloud? A) evaporation B) transpiration C) condensation D) precipitation

What two purposes does semen have?

Select the expression that is equal to (9c+3) - (5x-7) 14x-4 14x + 10 4x-4 4x + 10

What is the term for the net force directed toward the center of an object's circular path? a. circular force c. centripetal force b. centrifugal force d. orbital force Answer:c. centripetal force