If you pulled a wagon, what type of force would you provide?

A.
net force

B.
applied applied

C.
frictional force

D.
balanced force

d. platinum would have the greatest temperature increase because it has the lowest specific heat.

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 =

3. dark matter

empty space could also be a simple vacuum