Question 2 Multiple Choice Worth 2 points)

A substance has a half-life of 100,000 years and an initial mass of 1,000 grams. How many years will pass before only 250 grams of the substance's parent material is left?
A) 10,000
B) 50,000
C) 200,000
D) 300,000

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

answer'(basidium)the spore--bearing structure of a basidiomycete is called a basidiocarp; ///

it enhances antibody production by t cells of the adaptive immune system.

hope i'm right

explanation:

b. read the phase at the intersection of any given temperature and pressure.