The tomato plant and the oxalis plant both achieve a maximum CO2 utilization rate. Why do you think higher and higher light intensities do not cause an ever increasing rate of CO2 use?

b. lithosphere, asthenosphere, mesosphere   is the answer most likely

the cost of mining is extremely low compared to the money earned from mining, creating income to improve the environment.

if you listed your answers right then i believe your answer is b.