Which type of rock forms as a result of cooling and crystallization?
a. igneous
b . classic
c . metamorphic
d. sedimentary

Igneous rock is the type of rock that forms as a result of cooling an crystallization

Explanation:

Rocks are either sedimentary, igneous or metamorphic based on the chemical composition and the mode of formation.Igneous rocks are formed as a result of the cooling and crystallization of magma from volcanic eruptions. Igneous rocks are either intrusive, which form deep in the crust or extrusive which form on the surface of the earth.Sedimentary rocks are formed as a result of deposition, and cementation of sediments.Metamorphic rocks, on the other hand, are formed from the sedimentary and igneous rocks during the rock cycle.

Answer : option a) 84explanation :

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.

Acidichope this