It's lead. That's why the "apron" is so heavy.
D. Redefine the machine’s system boundaries.
The Law of Conservation of Energy states that energy can't be created not destroyed. Energy, however, can be changed from one form to another. The law applies to isolated systems only. By redefining and expanding the system (including all factors affecting it) , the machine's ability to do work should improve.
Explanation:
Crumple zones are sections in cars that are designed to crumple up when the car encounters a collision. Crumple zones minimize the effect of the force in an automobile collision in two ways. By crumpling, the car is less likely to rebound upon impact, thus minimizing the momentum change and the impulse.
To increase the number of snowmen destroyed, you would want more energy and all of the above would increase the energy of the system so D.
Has a skateboard. your gonna have to give more details the. that just one .
