To check whether a function is odd or even, we simply substitute the argument by its negative version, namely "x" by "-x".
if the expression simplifies to resemble the original expression, that simply means the expression is
even. If it resembles the original negative expression, is
odd.

well, that doesn't look like the original
- 2x³ - 9, so is not
even.
and -f(x) would be
2x³ + 9, and that doesn't look like either, so is not
odd.
thus is neither.
They would be able to clean 7 cars in 56 mins
Correct question with correct options has been attached
Answer:
37
Step-by-step explanation:
Let C represent those dressed as heroes and let B represent those wearing mask
Thus;
n(C) = 39
n(D) = 45
We are told that 21 entrants were dressed as heroes wearing a mask.
Thus; n(C n D) = 21
We are also told that there were a total of 100 entries.
Thus, n(T) = 100
Now, number of entrants neither dressed as heroes nor wearing a mask is given by;
n(T) - n(C u D)
n(C u D) = n(C) + n(D) - n(C n D)
n(C u D) = 39 + 45 - 21
n(C u D) = 63
Thus;number of entrants neither dressed as heroes nor wearing a mask is: 100 - 63 = 37