2red and 2 blue overlapping balls in the center are surrounded by a green, fuzzy, circular cloud with a white line running through it. 2 green balls sit on the white line, and a line leading a bracket around the balls is labeled a. a line leading to a bracket overlapping the white line is labeled b.
which is a characteristic of the part of the atom marked "a”?

it contains most of the mass.
it is negatively charged.
it is mostly empty space.
it is composed of electrons

the rearrangement of particles in a physical change. hope this

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 =