Which questions would help determine whether an article is scientifically accurate? Is the author stating an opinion or a fact?
Does the author have a balanced diet?
Does the author have evidence for the given facts?
How many articles has the author written before?
Does the author like music?

a 2,000 calorie based diet.

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 =