What is the surface area of sphere with radius 13 ft?
676π ft2
2704π ft2
208π ft2
52π ft2

Surface area of a sphere=

Step-by-step explanation:

the surface area of sphere with radius 13 ft

Surface area of a sphere formula is

Where 'r' is the radius of the sphere

r= 13 ft

plug in the radius and find surface area

Surface area of a sphere =

=

= square feet

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional

slope is 35 and 20 miles is the y-intercept.

step-by-step explanation: