Final answer:
It is generally recommended for children under the age of 13 to sit in the backseat, regardless of whether there is an airbag or not.
Step-by-step explanation:
The question is asking at what age it is better to sit in the back if there is an airbag. Airbags are designed to minimize serious injuries to passengers in case of an impact. It is generally recommended for children under the age of 13 to sit in the backseat, regardless of whether there is an airbag or not. This is because the force of the airbag deploying can be harmful to young children, and they are safer in the backseat where they are further away from the airbag.