This is the world’s coldest biome. it receives only 6-10 inches of precipitation per year and has a permanently frozen layer of earth called permafrost. the soil is nutrient-poor with very little vegetation.
a.
taiga
b.
tundra
c.
deciduous forest
d.
alpine

The answer would be:

b. Tundra

Here is more about the Tundra Biome:

The word Tundra comes from the Finnish word "tunturia," which means the treeless plain. It is quite accurate because there is little precipitation in this biome and it is always frozen, vegetation is very limited. The nutrients in the soil is mainly from dead organisms. It is high in nitrogen and phosphorus.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.