Describe why the shape of the moon appears to change over time. A)The moon is changing shape as it orbits around Earth and the sun.

B)The moon creates more light as it changes its position around Earth.

C)The sun orbits Earth, giving off different amounts of light to the moon.

D)The sun is lighting up different parts of the moon during the moon's orbit around Earth.

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 =