$2\mathrm{.}1$ Consider the following diagram and write the corresponding gradient expression.

$2\mathrm{.}1\mathrm{.}1$ Identify in the plot the variable represented by the letter

$2\mathrm{.}1\mathrm{.}1\mathrm{.}1$ A$.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}2$ B$.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}3$ Identify the process occurring at $C.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}4$ Identify the process occurring at $D.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}5$ Explain the meaning of graph $E.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}6$ Explain the meaning of graph $F.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}7$ Explain the meaning of graph $G.$

$2\mathrm{.}1\mathrm{.}1\mathrm{.}8$ Identify regions I, II$,$ and III.