The sun transfers energy to the earth by radiation at a rate of approximately 1.00 kw per square meter of surface.

a. if this energy could be collected and converted to electrical energy with 24 efficiency how large an area (in square kilometers) would be required to collect the electrical energy used by the united states? ( joules per year).

b. if the solar collectors were arranged in a square array, what would be the length of its sides in kilometers and in miles?

with all parts

1320336992.2512 m²

1320.33 kilometers or 509.79 miles

Explanation:

Energy transferred by the sun

Energy required by the United States is (assumed)

Power

Area

Area of the solar collector would be 1320336992.2512 m²

Converting to km²

Converting to mi²

Each side of the square would be 1320.33 kilometers or 509.79 miles

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 =