15 volume of the fish tank
 
        
             
        
        
        
Answer:
   13.98 in²
Step-by-step explanation:
I don't understand it, either. 
Point N is part of a "segment" that above and to the right of chord MO. It is the sum of the areas of 3/4 of the circle and a right triangle with 7-inch sides. The larger segment MO to the upper right of chord MO has an area of about 139.95 in², which <u>is not</u> an answer choice.
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The remaining segment, to the lower left of chord MO does not seem to have anything to do with point N. However, its area is 13.98 in², which <u>is</u> an answer choice. Therefore, we think the question is about this segment, and we wonder why it is called MNO.
The area of a segment is given by the formula ...
   A = (1/2)(θ -sin(θ))r² . . . . . . where θ is the central angle in radians.
Here, we have θ = π/2, r = 7 in, so we can compute the area of the smaller segment MO as ...
   A = (1/2)(π/2 -sin(π/2))(7 in)² = 24.5(π/2 -1) in² ≈ 13.9845 in²
Rounded to hundredths, this is ...
   ≈ 13.98 in²
 
        
             
        
        
        
Answer:
15x+20y+5z
Step-by-step explanation:
Trust me.
 
        
             
        
        
        
40,44,48,52,56,60,64,68,72,76,80.........