11 Steve has a basket with marbles: one red, one blue, and one white. He randomly selects a marble and records the color.
He places the marble back into the basket, randomly selects another marble, and records the color. Which tree diagram
represents the sample space of the experiment

because growing process had stoped after 4-5 year

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 =