32) a bicyclist starts a timed race at 6.0 mi/h. in order to win, he must average 21 mi/h. assuming
constant acceleration from the start, how fast must he be traveling at the end of the race?
a) 24 mi/h
b) 36 mi/h
42 mi/h
d) 30 mi/h

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 =