Which of these is a benefit of nuclear energy?
a. nuclear materials can be dangerous.
b. nuclear waste must be carefully managed.
c. nuclear energy is easy to use and transport.
d. nuclear power provides huge amounts of electricity.

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 =