(-1) + (-1) + (-1) + (-1) + ... 500 times =
(a) 500
(b) 1
(c) -1
(d) -500

D

Step-by-step explanation:

(-1) + (-1) = -2... so 500 times... it would be -500.

15

step-by-step explanation:

we are given the following expression and we are to solve it and find the product:

-13 × (-5)

solving the given expression in the standard order of solving a mathematical expression, beginning with the opening of brackets and then multiplying the terms and changing their signs.

-3 × -5 = 15 (answer is positive because when negative is multiplied with negative, it gives a positive answer)