Answer:

Step-by-step explanation:
observe
||a–b+c|| = ||a+b+c||
(a-b+c)² = (a+b+c)²
(a+b+c)² – (a-b+c)² = 0
((a+b+c)+(a-b+c))((a+b+c)–(a-b+c)) = 0
(2a+2c)(2b) = 0
(a+c)b = 0
a•b + c•b = 0
||a||×||b||×cos(π/8) + ||c||×||b||×cos(θ) = 0

Edit: Misread the diagram, the previous answer was wrong.
Answer:
The answer is 18x.
Step-by-step explanation:
2x times 9 is 18x because when you multiply 9 times 2, you get 18 and the x carries over.
The directions say round to the nearest tenth so use the 8.8 cm
We know that
the axis is equal to the diameter of a sphere
so
D=14 units
r=D/2-----> r=7 units
<span>the surface area of the sphere=4*pi*r</span>²------> 4*pi*7²=196*pi units²
the answer is the option
<span>C. 196 pi units^2</span>