Which of the following sources of indoor pollution is not likely to be carcinogenic? a. asbestos b. inhalable particulates c. carbon dioxide d. volatile organics e. radon

i think it is non rem sleep

are there answer choices to this question? this seems like a question where you have options to choose from.

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 =