Can somebody help me find what x is?
x =

a.5
b.10
c.6

Organisms that live in the alpine and taiga biomes have developed unique adaptations that aid in their survival. the douglas-fir is a conifer tree that grows in the taiga biome. it has an average height of about 70 feet, and its wood is an important source of lumber.

Aflute is on sale for 20% off. including the discount and 8% tax, the sales price is $216.

Simplify the expression. -2/5(10+15m-20n)