Which scenario describes a systematic error? A person bumps the table as a volume is measured.
A measurement is recorded before a balance comes to rest.
A thermometer reads 0.1 degree higher than it should.
An incubator unexpectedly loses power for ten minutes during the night.

the area between the graph and the t axis

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 =