Answered

Choose the correct form: The proportion of cars which (use/uses) unleaded petrol (is/are) smaller than that of all other cars.

Sagot :

Rodriguezmina94viz
The proportion of cars that uses unleaded petrol is smaller than all the other cars.

Explanation: Because then subject "proportion of cars" is a collective noun, and collective nouns use singular verbs.
Diceviz
uses and are are my answers