The circuit is working, and all three bulbs are lit. If a switch at A is opened, what will happen to the circuit?
A. All three bulbs will stay lit.
B. All three bulbs will go out.
C. Bulb 1 will go out, but bulbs 2 and 3 will remain lit.
D. Bulbs 1 and 2 will go out, but bulb 3 will remain lit.

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.

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 =