It’s simple. The volume of a sphere is V=4/3πr^3.. so you will convert the mm to m okay?? 10mm=1cm .. so do your conversion from here then when you get the radius then you will substitute it into the volume where r is the radius.. so for the first one l changed mm to cm so.. radius is 4cm then l substitute it into the formula so l got 270 after rounding it to the nearest tenth.. pi=22/7 bear in mind. So do the same for the other one
        
             
        
        
        
Answer:
2 2/3
Step-by-step explanation:
hope this helps :)
don't be afraid to ask questions 
 
        
                    
             
        
        
        
The answer is  7/8
Hope the helps:)
        
                    
             
        
        
        
Answer:
Perimeter of the square field is 600 meters.
Step-by-step explanation:
Given:
Area of a square field = 2.25 hectares
1 hectare = 10000 m²
∴2.25 hectares = m²
 m²
Now, let each side length of the square field be  meters.
 meters.
∴ Area = 
⇒ 
⇒  m
 m
Now, perimeter of a square is given as,  .
.
Here,  m.
 m. 
∴  m
 m
Hence, the perimeter of the square field is 600 meters.
 
        
             
        
        
        
9514 1404 393
Answer:
   x = ±3√2i
Step-by-step explanation:
Add -18 to both sides of the equation:
   x^2 = -18
Take the square root of both sides:
   x = ±√(-18)
Remember that 18=9·2 = (3^2)·2 and √-1 = i. Simplify.
   x = ±(√(3^2))·(√2)·(√-1)
   x = ±3√2i