In $ECG$,the $T$-wave represents:

Complete the missing words in the statements given below:
$(a)$ Plasma without clotting factors is called serum.
$(b)$ $.........$ and monocytes are phagocytic cells.
$(c)$ Eosinophils are associated with $.........$ reactions.
$(d)$ $.........$ ions play a significant role in clotting.
$(e)$ One can determine the heart beat rate by counting the number of $.........$ in an $ECG$.

In the following diagrammatic representation of a standard $ECG$,the '$T$' wave represents:

In all the leads of $ECG$,all following are positive waves except

Rise in blood pressure is directly related to the following $EXCEPT$ . . . . . . .

Select the correct option for $ECG$.