If one recessive allele and one dominant allele are present, the trait will be expressed.
a. original
b. main
c. dominant
d. recessive

i am going to guess that it is co2.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.