If you attach a 150 g mass to the spring whose data are shown in the graph, what will be the period of its oscillations? A) 0.49 s
B) 0.08 s
C) 15 s
D) 2.4 s

grav potential energy

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 =