Answer:
-3, 17
Step-by-step explanation:

There is no relation between the size of a lake and the number of fish in the lake.
(the number) - 2 = 25
(the number) = 25 + 2
(the number) = 27
1.

4 + 7 or 4 - 7 = 11 or -3
2.
pi is a real number. It is not imaginary or complex, so it definitely belongs to the set of real numbers.
pi is not a whole number or a rational number. It cannot be written as a fraction of integers. pi is irrational.
Therefore, pi is real and irrational.