Y=4 pls brainliest me thanks
        
                    
             
        
        
        
The ratio is 4:3:1
let the ratio be 4x:3x:x
according to the question,4x+3x+x=40
8x=40
x=5
therefore amount of gravel=x*4=5*4=20

amount of sand=5*3=15

amount of cement=5*1=5
 
 
        
        
        
C is the correct answer because triangles always equal to 180 degrees
        
                    
             
        
        
        
Answer:
The radius is 9 mm
Step-by-step explanation:
The volume of a sphere is given by
V = 4/3 pi r^3  where r is the radius
972 pi  = 4/3 pi r^3
Divide each side by pi
972 = 4/3 r^3
Multiply each side by 3/4 to isolate r^3
3/4 * 972 = 4/3 * 3/4 r^3
729 = r^3
Take the cube root of each side
(729) ^ (1/3) = (r^3) ^ (1/3)
9 = r
The radius is 9 mm