When ever you combine different elements the chemical properties change because elements are different , unless you combine the exact same elements.
Step-by-step explanation:
I don't know if the first set of numbers is all in one set, but I'll do my best to give you an answer.
Really all you need to do is use PEMDAS for the first question.
(Parentheses, exponents, multiply, divide, add, subtract. In that order)

Then to simplify that fraction next to it, notice that 0.018 is 3x 0.06.
that's a 3:1 ratio, so it ends up simplifying to this:

Lastly, to solve the division of that fraction. If you divide by a fraction, you multiply whatever it's dividing by its inverse.
So...

Step-by-step explanation:
step 1. a polynomial must have whole non negative exponents
step 2. A, B, D have negative exponents
step 3. C is a polynomial.