Lifting a book off a shelf. Positive, Negative, or Zero work? (75 points)

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

i think they are all correct

explanation:

they seem good

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 =