This would be a great question to just plug into a calculator. I'm sure you will find the answer quite easily if you use a calculator.
Answer:
40k+45m
Step-by-step explanation:
5(8k)=40k + 5(9m)= 45m
ANSWER

EXPLANATION
A) From the diagram, we see that the base of the triangular face is 4 cm long and the height of the triangular face is 3 cm.
B) From the diagram, we see that the length of two of the rectangular face is 15 cm and the width of the rectangular face is 5 cm.
The third rectangular face has a length of 15 cm and a width of 4 cm.
C) The surface area of the prism is the sum of the areas of the faces of the prism.
The area of a triangle is given as:

where b = base, h = height
The area of a rectangle is given as:

where l = length, w = width
Therefore, the surface area of the prism is:
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