I'm sorry but I'm not into square roots yet :(
        
                    
             
        
        
        
Answer:the pages will come on the first is  210
Explanation:
Since we have given that two pages that face each other in a book 
i.e. they must be consecutive to each other 
so, let the first page number be x
and the second page number be x+1
According to question, 

2x=421 -1
2x=420

So, the pages will come on the first is  210
 
        
             
        
        
        
Answer and explanation:
Farmer's number of apples = 96 apples
Given that Farmer needs to bag the apples so that there are at least 4 apples in each bag(not less than 4 apples in each bag) and not more than 10 apples in each bag
And also all apples in each bag are equal
We need to find the numbers between 4 and 10(including 4 and 10) that can divide 96 without a remainder 
4 can divide 96= 24
5 cannot divide 96 without remainder 
6 can divide 96 =16
7 cannot divide 96 without remainder 
8 can divide 96=12
9 cannot divide 96 without remainder 
10 cannot divide 96 without remainder 
From the above we see that the factors of 96 = 4, 6, 8 between 4 and 10
4 apples = 24 bags 
6 apples = 16 bags 
8 apples = 12 bags
Therefore, there can be 3 possible ways of having equal number of apples in each bag between 4 and 10 apples
 
        
             
        
        
        
-- The two sides of a right <u>angle</u> intersect and make the angle. 
So do the sides of any other angle. So they can't be parallel.
-- No two sides of a right <u>triangle</u> ... or any other triangle ...can be parallel.
        
             
        
        
        
Answer is (d) P, Q , R
Any triangle has 3 vertices , after which its name is justified