Answer:
I think the answer is letter A.
Using the distributive property we know we distribute by multiplying the outside values to those inside of the parentheses
outside values: 2
inside values: 5 and r
now multiply out inside values by the outside values
2x5 = 10
2xr = 2r
now plug these values back in for the inside values and take away the outside value and the parentheses
so 2(5+r) using the distribution property is 10+2r
All internal angles in a quadrilateral add to 360
so
x+110+110+70=360
x+290=360
minus 290 both sides
x=70 degrees
Answer:

Step-by-step explanation:
Given: Perimeter of base of a pyramid = 12.8 m
Height of the pyramid = 12.5 m
To find: volume of a pyramid
Solution:
Perimeter of base of a pyramid = 12.8 m
As base of the pyramid is a square,
12.8 = 
side of a square = 
Area of a square (A) = 
Height of the pyramid (h) = 12.5 m
Volume of the pyramid = 