Give three characteristics of a series circuit.

A child has drawn the electric circuit to study Ohm's law as shown in figure. His teacher told that the circuit diagram needs correction. Study the circuit diagram and redraw it after making all corrections.

Three $2$ $\mathrm{\Omega }$ resistors. A, B and C, are connected as shown in figure. Each of them dissipates energy and can withstand a maximum power of $18\mathrm{W}$ without melting. Find the maximum current that can flow through the three resistors?