Which metals are used as an anode and a cathode in a $Daniell$ 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

The limiting molar conductivity $\Lambda^o$ for $NaCl$,$KBr$ and $KCl$ are $126$,$152$ and $150 \ S \ cm^2 \ mol^{-1}$ respectively. The $\Lambda^o$ for $NaBr$ is (in $S \ cm^2 \ mol^{-1}$).

What is a primary battery? Provide a note on primary batteries and a note on dry cells.

Calculate $\Delta G^{\circ}$ for the reaction $Mg_{(s)} + Sn_{(aq)}^{2+} \longrightarrow Mg_{(aq)}^{2+} + Sn_{(s)}$ if $E_{cell}^{\circ}$ is $2.23 \ V$. (in $kJ$)

In the experiment set up for the measurement of $EMF$ of a half-cell using a reference electrode and a salt bridge,when the salt bridge is removed,the voltage