A laser with power output of 2.0 mW at a wavelength of 400 nm is projected onto a Calcium metal. The binding energy is 2.31 eV. i. How many electrons per second are ejected? [6 marks] ii. What power is carried away by the electrons? [4 marks]

d. air pressure decreases as altitude increases.

because growing process had stoped after 4-5 year

it's a b and

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 =