Increase in $CO_2$ concentration around the leaf results in:

In the eastern states of India,rice production decreases during the monsoon season. Which factor is primarily responsible for this?

Maximum solar energy may be trapped by

$A-$ The $C_3$ and $C_4$ plants respond differently to $CO_2$ concentrations.
$R -$ The concentration of $CO_2$ in the atmosphere is between $0.03$ and $0.04$ percent. An increase in concentration up to $0.05$ percent can cause an increase in $CO_2$ fixation rates.

Photosynthetic yield is maximum at the

If plants are given only visible light,their growth will: