In the light reactions, electrons from replenish chlorophyll molecules that have given up electrons.

water

 The light reactions of noncyclic photophosphorylation takes place in the chloroplast. The light energy is converted to chemical energy to produce both ATP and NADPH, which act as energy-transfer molecules in the light-independent reactions of the Calvin cycle. The addition of phosphate due to synthesizing of ATP by cells results to photophosphorylation.

Moreover, the electrons from water replenish chlorophyll molecules that have given up electrons by photolysis. The two electrons from the water molecule are kept in photosystem II, while the 2H+ and 1/2O2 are left out for further use.

.

i think the answer is tomato juice? not entirely sure though

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 =