Factorial zero; Power of zero; Infinity

[Lisasmith111]

Hello folks,

Although 0! = 1 can anyone explain why this is the case. Hopefully, in a simple way so that I can understand why this is the case.

Also why does anything to the power of zero = 1 eg 10^0 = 1 and 9^0 = 1.

Finally, we all act as though we understand infinity even though none of us really know what it is. Can anyone explain?

Kind regards

Lisa Smith