The current "i₄" in the circuit of Fig. is equal to

The voltage V in Fig. is

The voltage V in Fig. is always equal to

In the circuit of Fig. when R = 0 Ω, the current i_R equals 10 A.

(a) Find the value of R for which it absorbs maximum power.

(b) Find the value of E.

(c) Find v2 when R = $$\infty$$ ( open circuit)