A 15,000 kg railroad car is moving to the west with a speed of 5.4 m/s. If a locomotive performs 1,775,000 J of work on the railroad car by applying a westward force to the railroad car, what is the final speed of the railroad car?

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 =

it is b. absorbs thermal energy