$7.18 / 2 = $3.59 per pound
.........................................
so 1 lb = $3.59
2 lbs = 2* $3.59 = $7.18
3 lbs = 3 * $3.59 = $10.77....
        
             
        
        
        
The answer you want is 20!
        
                    
             
        
        
        
Here’s my work to your question!
 
        
        
        
Answer:
Step-by-step explanation:
Hence, the surface area of a triangular pyramid is 140 square units.