If you move the decimal point left until it is just to the right of the most-significant digit, the number of places you moved it is the power of ten that your new number is multiplied by.

Then multiplication can proceed in the usual way, taking into account the rules of exponents.

0.013413582325191 got it from google
No - It is a function.
A relation which is not a function has more than 1 output for an input.
4+3(7+4 x 2)-100
4+3(7+8)-100
4+3(15)-100
4+45-100=
-51