Calculate the electricity bill amount for the month of April if $4$ bulbs of $40 \, W$ for $5 \, hrs$, $4$ tube lights of $60 \, W$ for $5 \, hrs$, a $TV$ of $100 \, W$ for $6 \, hrs$, and a washing machine of $400 \, W$ for $3 \, hrs$ are used per day. The cost per unit is ₹ $1.80$.

(D) Energy consumed is given by $E = P \times t$.
Energy consumed by $4$ bulbs per day $= 4 \times 40 \, W \times 5 \, hrs = 800 \, Wh$.
Energy consumed by $4$ tube lights per day $= 4 \times 60 \, W \times 5 \, hrs = 1200 \, Wh$.
Energy consumed by $TV$ per day $= 100 \, W \times 6 \, hrs = 600 \, Wh$.
Energy consumed by washing machine per day $= 400 \, W \times 3 \, hrs = 1200 \, Wh$.
Total energy consumed per day $= 800 + 1200 + 600 + 1200 = 3800 \, Wh$.
Since April has $30$ days, total energy consumed in April $= 3800 \, Wh \times 30 = 114000 \, Wh$.
Converting to units $(kWh)$: $114000 \, Wh / 1000 = 114 \, kWh$ (or $114$ units).
Total electricity bill $= 114 \, \text{units} \times ₹ 1.80 / \text{unit} = ₹ 205.20$.