What will be the unit digit of the square of 7992​

4

Step-by-step explanation:

Here you need not completely solve 7992 squared. You can just take the last digit which in this case is 2 and solve for the square of that digit. 2 x 2 = 4. Now if it was a bigger digit which would result in a two digit number when squared you would take the last digit of that number. But, we don't need to do that here since 2 squared is 4.

(d)

step-by-step explanation:

given: the line in the graph passes through points (5,30) and (6,26).

then, the equation of line is:

now, put y=a(n) and x=n,

hence, option d is correct.