Which statement about hail is correct? a. it is rain that falls through a layer of freezing air. b. it may freeze at high elevations many times before falling to the earth. c. it forms in winter in low stratus clouds. d. it is a liquid form of precipitation.

The correct option is It may freeze at high elevations many times before falling to the Earth

Hail are pellets of frozen rain which fall in showers from cumulonimbus clouds. Hail forms when thunderstorms are strong enough to carry water droplets well above the freezing level. This freezing process forms a hailstone, which can grow as additional water freezes. Eventually, the hailstone becomes too heavy for the updrafts to support it and it falls to the ground.

the components of a vector are the parts of the vectors that are to each other.

b perpendicular

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =