Phosphoenol pyruvate $(PEP)$ is the primary $CO_2$ acceptor in

In $C_{4}$-pathway,the first product identified was

Compared to $C_3$ plants,how many additional $ATP$ molecules are required to produce one molecule of hexose in $C_4$ plants?

Choose the correct statements regarding $C_4$ plants:
$(1)$ $C_4$ plants do not tolerate higher temperatures.
$(2)$ $C_4$ plants show a response to high light intensities.
$(3)$ $C_4$ plants lack a process called photorespiration.
$(4)$ Productivity of $C_4$ plants is less than $C_3$ plants.
$(5)$ $C_4$ acid $OAA$ is formed in the mesophyll cells.

By looking at which internal structure of a plant can you tell whether a plant is $C_{3}$ or $C_{4}$? Explain.

Find the odd one out with respect to double carboxylation.