Find the unique four-digit integer n with these properties:

the last digit (the units digit) of n is 9.

the digits of n add up to 27.

two digits of n are the same.

n is a perfect square

The number is 3969.
It is the square of 63

In the first triangle 80+20+p=180 (since sum of all angles of a triangle is 180)so p= 80also in second triangle 55+45+q=180 (since sum of all angles of a triangle is 180)so q=80so we can conclude that p=80 degrees q=80 degrees so p=q=80 degreeshence option b is correct