A (A right triangle with a side length of 5 and hypotenuse with length \sqrt{74})
For this case we have by definition of trigonometric relations of rectangular triangles that, the sine of an angle is given by the opposite leg to the angle on the hypotenuse of the triangle. Then according to the figure we have:

We cleared CA:

Answer:
Option A
Answer:

Step-by-step explanation:
The formula for the surface area of a pyramid is 
Answer: i think the answer is (A)
Step-by-step explanation:
I recalculated and the other person was correct, sorry for the mix up