Answer:
A. None of these
Step-by-step explanation:
The largest perfect square under 100 would actually be 81 (9 x 9)
90 and 99 are not perfect squares and 64 is smaller than 81.
 
        
                    
             
        
        
        
Step-by-step explanation:
We are picking 6 numbers from the numbers 1,2,3,4,5,6,7,8,9,10. Since we care about numbers being next to each other, we might think of the 10 numbers as being distributed in 5 boxes (which you can think of as the holes):
|   1 2   |   3 4   |   5 6   |   7 8   |   9 10  |
So on the first box we have the numbers 1 and 2, on the second box we have the numbers 3 and 4, and so on. Since we are picking 6 numbers from those 10 numbers, that means we'll have to pick 6 boxes (and inside each box we pick a number), but we only have 5 available boxes, so by the pigeonhole principle, we'll have to pick 1 same box at least two times. Since on each picked box we'll need to pick a number, on this box which was picked two times, we will have to pick both of its numbers. And so those 2 numbers inside that box will be next to each other (meaning they're consecutive numbers). 
 
        
             
        
        
        
= 198 x (1 + .20)
= 198 + 39.6
= 237.6
I hope this helps!
        
             
        
        
        
Answer: 390 calls
Step-by-step explanation: 
13/2= 6.5
6.5 x 60 min= 390
 
        
             
        
        
        
Well it would equal 0.55 because 5.50-10%=5.50