Answer:
it floats because the lake is cold at that moment so when part of the lake freezes it still remains solid and floats because of the lake and the surrounding of the lake is still cold
A standing wave is the result of a reflection.
If iron were used to make coins then it would rust easily,because of its exposure to water, air etc..
I think it's a) 1st Newton's law... so sorry if it's wrong...
