Which of the following statements are true for fuel cells?

For the cell reaction,$Zn + Cu^{2+} \to Zn^{2+} + Cu,$ the cell representation is:

In an electrochemical cell,

$A$ depolarizer used in dry cell batteries is

Write a note on hydrogen-oxygen fuel cell.

The correct statement/s about a Galvanic cell is/are:
$(a)$ Current flows from cathode to anode
$(b)$ Anode is the positive terminal
$(c)$ If $E_{cell} < 0$,then it is a spontaneous reaction
$(d)$ Cathode is the positive terminal