How would an electron shell model of an oxygen atom (O) appear after the atom has formed chemical bonds? It would have six electrons in the outermost shell.
It would have six electrons in the innermost shell.
It would have eight electrons in the outermost shell.
It would have eight electrons in the innermost shell.

answer: its c lololo

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 =