The answer is D.
(Edited to combat confusion)
Dams are important because:
They provide water for domestic, industry and irrigation purposes.
Dams often also provide hydroelectric power production and river navigation.
Domestic use includes everyday activities such as water for drinking, cooking, bathing, washing, and lawn and garden watering.
Dams and their reservoirs provide recreation areas for fishing and boating.
They help people by reducing or preventing floods. During times of excess water flow, dams store water in the reservoir; then they release water during times of low flow.
Answer:
15 inches
Explanation:
James needs to use the Pythagoras theorem, which states that in a right-angle triangle, the sum of the squares of the other two sides is equal to the square of the hypotenuse.
c²=a²+b²
we know that a is 9 inches and that be is 12 inches
c²= (9)²+(12)²
c²= 81+144
c²=225
c=√225
c=15
after applying the measures to the Pythagoras theorem formula,
we found out that the length of the straight-edge needs to be 15 inches