4. If a galaxy is 300,000 light years from Earth. How long did it take for light from that galaxy to reach Earth?
c. 300,000 years
300 days
d. 300,000,000 years
b.
300 years

the components of a vector are the parts of the vectors that are to each other.

b perpendicular

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 =