Me solve these 2 questions that's shown in this picture

I can't see the complete picture, but I know the #2 is either C or D. You simply get one of the expressions and multiply it by 2 (because of its opposite side.)
And once you've done that for both expressions, add that together and you have your answer. Hope that helped.

1) You are basically factoring -4x - 24 by choosing the GCF of the two terms (-4x and -24). The GCF is -4. To figure out the terms inside of the parenthesis you need to divide both of the original terms (meaning -4x and -24) by 4. So -4x/-4 = x and -24 / -4 = 6. 
-4(x + 6) 

2) To find the perimeter of a rectangle we multiply the width and length each by 2 (P = 2W + 2L) 
Length = x + 13
Width = x 
P = 2(x) + 2(x + 13) 
P = 2x + 2x + 26
P = 4x + 26

Element 17 is chlorine it is a group 7 element(halogen) and belongs to period 3 of the periodic table