The average atomic mass of boron is 10.81 amu. Based on the atomic mass of B-10 and the relative abundances of the boron isotopes, what is the atomic
mass of B-11?
Isotope
Atomic mass (amu)
Relative abundance (%)
B-10
10.013
19.9
B-11
80.1
O A. 12.434 amu
OB. 11.009 amu
O C. 11.801 amu
O D. 9.084 amu

? you expect us to answer this? ? this is your schoolwork, i don't think we can with this, i think it would considering being

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.

1.solid

2.carbon dioxide

3.helium

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.