Which is the geometric mean between 81 and 4

The GM of 81and4, by definition, is √81×4=18 .

exploitation:

geometric mean of a and b = square root of (axb).

the correct answer is sex-linked recessive.

i just took the test

the atmospheric gas that forms a mild acid when dissolved in water is called carbon dioxide. the correct answer is a. 2.) chemical weathering would cause an inscription on a marble headstone to become harder and harder to read over time.