The problem was too big to type in my phone.
I hope my answer is readable.
P.S After the collision P is also moving in the same direction as Q.
There are no appropriate units for power on the list you provided
They both have momentum but the car traveling at 50 m/s has more momentum because of the speed difference
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Answer:
has free electrons
Explanation:
A conductor has free electrons while an insulator does not. Free electrons are electrons which are not bounded tightly to their parent atoms, and are free to move given the right conditions (ie. a strong EM field).