You need 9.6 ml of plastic resin to mould a drum. How many litres do you need to produce 50 000 drums?

Each drum requires $9.6 \text{ ml}$ of resin.
To produce 50,000 drums, the total volume needed is:

$$\text{Total volume (ml)} = 9.6 \text{ ml/drum} \times 50,000 \text{ drums}$$ $$\text{Total volume (ml)} = 480,000 \text{ ml}$$

We know that $1 \text{ litre} = 1000 \text{ ml}$.
To convert milliliters to litres, we divide by 1000:

$$\text{Total volume (L)} = \frac{480,000 \text{ ml}}{1000 \text{ ml/L}}$$ $$\text{Total volume (L)} = 480 \text{ L}$$

The total amount of plastic resin needed is $480 \text{ litres}$.

The correct option is $\text{480}$.