A right triangular prism and its net are shown below.
(All lengths are in centimeters.)

Answer:
Below in bold.
Step-by-step explanation:
a) The rectangle in the middle of the net is 10 cm long.
A = 8
B = 3
C = 6
D = 10
b) Surface area
= 3*6 + 3*10 + 3*8 + 2 * 1/2 + 8 * 6
= 18 + 30 + 24 + 48
= 120 cm^2
[tex]sa = bh + ( b_{1} + b_{2} + b_{3})l[/tex]
[tex]sa = 6(8) + (6 + 8 + 3) \times 10[/tex]
[tex]sa = 48 + (17)(10)[/tex]
[tex]sa = 48 + 170[/tex]
[tex]sa = 220 \: {cm}^{2} [/tex]