Answer:
400cm²
Step-by-step explanation:
Total surface area of a prism includes the area of the top and bottom triangle sides of the prism, plus the area of all 3 rectangular sides.
Base & Bottom triangle area: 2 x [(8 x 15)/2] = 120cm²
Side triangle area: 17 x 7 + 8 x 7 + 15 x 7 = 280cm²
Total surface area = 280 + 120 = 400cm²
8 is the answer because we all ķnow 3 ×8=24
104 and 105 are consecutive numbers that add up to 209. Maybe this answers your question? Let me know otherwise.
6 hours to 1 book is a unit rate because the independent variable (books) is equal to 1.
Hope this helps!