Which of these types of rock form near earths surface? select all that apply. a. igneous b. sedimentary c. metamorphic

A. Igneous

Extrusive igneous rocks cool and solidify quicker than intrusive igneous rocks. They are formed by the cooling of molten magma on the earth's surface.

Sedimentary (sed-uh-MEN-tuh-ree) rocks, unlike the other two kinds of rocks, are formed on or near Earth's surface. They form from sediments eroded from other rocks. The sediments may come from igneous, metamorphic, or other sedimentary rocks.

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 =