If you start at 100% and divide it by 2 it will equal 50% then divide by 2 again and the answer will be 25%. Your answer should be 25%
In theroy, yes. But time travel has yet to happen and thus, we dont know. I would assume that that if an alternate universe were NOT created, it would cause a rip in the fabic of time creating a worm hole and allowing all entitys to pass through simultaneously,and that would cause great stress on it, possibly causing it to rip large enough to encase the whole universe and it would implode.
Answer:
Angular frequency will increase
No change in the amplitude
Explanation:
At extreme end of the SHM the energy of the SHM is given by

here we know that

now at the extreme end when one of the mass is removed from it
then in that case the angular frequency will change

So angular frequency will increase
but the position of extreme end will not change as it is given here that the top block is removed without disturbing the lower block
so here no change in the amplitude
I'm quite certain the answer is "stress".