A boat leaves the dock and travels 9 miles due south, then 12 miles due west. How far is the boat from the dock A. 15 mi B. 21 mi C. 3 mi D. 225 mi

21 miles which is b

Step-by-step explanation:

no other answer makes sense besides that one.

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

the surface area is 124cm²

step-by-step explanation:

length: 4cm

width: 9cm

height:   2cm