What does the position of lithium (li) on the periodic table tell you about its tendency to react with other elements?

It is in the first column, so it tends to lose one electron.

Explanation:

(I just answered this question on my own as I couldn't find it on :/)

Anyways,

It is clear the lithium is in the first column, not the second row, so that already eliminates two of the four possible answers.

Lithium has 3 protons and 3 electrons. Meanwhile, elements further to the right of this element tend to have increasingly more protons/electrons. To become a stable bond, there must be a total of 8 electrons.

For example,

while lithium has 3 electrons, Nitrogen has 7. It needs one more to become stable. So Lithium will bond with Nitrogen and give it one of it's electrons for a total of 8.

6/12=1/2

step-by-step explanation:

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 =