How is the rate of an enzymatic reaction increased?

Enzymes,which catalyse the joining of $C-O, C-S, C-N, P-O$ etc. bonds,are included in which of the following classes?

Metabolic poisons which alter the structure of an apoenzyme are:

Given below are the statements regarding enzymes. Choose the correct statements.
$i$. All enzymes are proteinaceous.
$ii$. Enzyme becomes more active at the temperature of $60^{\circ}C$ to $70^{\circ}C$.
$iii$. Enzymes have one or two active sites where substrate binds with the enzyme.
$iv$. Any increase or decrease in specific $pH$,enzyme activity is always enhanced.
$v$. Enzymes remain active to catalyze again after completion of first reaction.

In feedback regulation,the metabolic pathway is inhibited by:

Which of the following is a competitive inhibitor of succinic dehydrogenase?