Answer:
The correct answer is 3.
Step-by-step explanation:
To help the environment carpooling or cycling more often is essential to reduce the emission of pollutant gases from the internal combustion of the engine, eliminated by the exhaust.
Recycling old batteries and phones is a good way to reduce the accumulation of electronic and hazardous waste such as batteries.
Using reusable grocery bags when shopping would help the plastic problem as an environmental pollutant.
Filling the tank with gasoline only when the tank is half empty would not cause a positive impact on the environment, as it would not reduce the emission of polluting gases.
Have a nice day!