It is crash-test-dummy Ed's first day on the job. He (and his 50-kg mass) gets to try out the new 1,200-kg Porsche 911. Lucky Ed! He has to drive it into a brick wall. Unlucky Ed! But it's his job, so he does it.

The Porsche and Ed are moving 30 m/s when they collide with the wall, with an impulse time of 0.5 s.

What is the magnitude of their initial momentum?