what is the product of 33 negative numbers and 2 positive numbers?

Every two negative numbers when multiplied together will result in a positive number. 

Therefore an odd number of negative numbers multiplied together will result in a negative number while an even number of odd numbers will result in a positive number.

Multiplying by a positive number never changes the sign.

So ask yourself, are there an even number of negative numbers (giving a positive answer) or an odd number of negative number (giving a negative answer).