| More following distance than driving with a single trailer | |
| More care when driving in bad weather and on grades | |
| All of these are correct | |
| More skill than driving with a single trailer |
| The longer the trailers you`re pulling the larger the effect | |
| The rearmost trailer is the most affected | |
| Another name for rearward amplification is the crack-the-whip effect | |
| The more trailers you`re pulling the larger the effect |
| Open both shut off valves | |
| Close the shut off valve at the rear of the first trailer and open the shut off valve at the rear of the second trailer | |
| Close both shut off valves | |
| Open the shut off valve at the rear of the first trailer and close the shut off valve at the rear of the second trailer |