Help I need to turn this in today:)

Total surface area

=2 ×(area of triangle) +( area of rectangle 1) + (area of rectangle 2) + (area of rectangle 3)

2×(1/2 × 16 ×12) + (10×12)+(16×10)+(20×10)

=672 cm²

1.4

2.3

step-by-step explanation:

the formula for the constant of variation is

y= kx

divide each side by x

y/x =kx/x

y/x =k

we know a and y

1.   y/x = k

4/1 =4

check the other values to make sure they are the same

8/2 = 4   12/3 =4   and 16/4 =4  

the constant of variation is 4

2.   y/x = k

3/1 =3

check the other values to make sure they are the same

6/2 = 3   9/3 =3   and 12/4 =3  

the constant of variation is 3

understand that i don't know the answers

will someone answer his question