Ok A is the correct answer
The mass of an ink pen with a triple beam balance if all the weights positioned to the right would be a maximum of 610 grams which sounds rather heavy for an ink pen but in the absence of necessary information it seems that that would have to be the answer.
Answer:
An increase in the amount of CO2 well increase the rate of photosynthesis, Carbon dioxide concentration will directly affect the rate of photosynthesis as it is used in the photosynthesis reaction.Increased amount of CO2 will increase the rate of photosynthesis to a certain limit, after which a further increase in its amount will no longer increase the rate any further.
Hope this helps.
Cheers! :)