Which one is the correct equation ?

Which one of the following equations is the correct equation for the electrical circuit shown in the figure ?

Which is the correct representation for Nernst equation :

Which one of the following equation is correct with respect to an ammeter ?

Which one of the following equation is correct for the circuit shown. The currents in each branch of circuit are indicated and all three cells are ideal

Which one of the following equation is correct for the circuit shown. The currents in each brach of circuit are indicated and all three cells are ideal.

Which one of the following equation is correct for the circuit shown. The currents in each branch of circuit are indicated and all three cells are ideal