Amachinist wishes to insert a copper rod with a diameter of 8 mm into a hole with a diameter of 7.993 mm. by how much would the machinist have to lower the temperature (in °c) of the rod to make it fit the hole?

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 =