Q1 FOR Z IS ????
Q3 FOR Z IS ???
You will need to post the questions if you expect someone to help you answer them...
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.
Welcome to the forum. Why hate it? It is a beautiful field.
If it ain't broke, fix it until it is.
A number by itself is useful, but it is far more useful to know how accurate or certain that number is.