Why do c4 plants keep their stomata closed on hot days

C4 plants are those plants that cycle carbon dioxide into four carbon sugar compound which enter into the Calvin cycle.  C4 Plants keep their stomata closed on hot days IN ORDER TO ELIMINATE WATER LOSS.
C4 plants are very efficient in hot and dry climates and they make a lot of energy.

If the experiment was perfomed more then once and you get the same results

When a virus infects a host cell, it uses the cell's machinery to make copies of its own genetic material in a process called replication. finally, during the process of self-assembly, that protein shell and the copies of the virus's genetic material are assembled into new viruses.