Graded $2$: State whether the light bulbs below are a$)$ in series b$)$ in parallel or c$)$ neither. Remember that if resistances are in series, the current through each must be the same. If resistances are in parallel, the voltage across each is the same since their ends are connected together:

Bulbs $1$ and $2$:

Bulbs $1$ and $3$:

Bulbs $2$ and $3$:

Branch with bulbs $1$ and $2$ and Bulb $3$:

Bulbs $1$ and $4$:

Bulbs $3$ and $4$: