The answer would be 78. C
A rational number is any number that can be represented as a fraction. (7=7/1 or 52 = 26/1 ).
An irrational number is a number like 3.14159 (pi) or anything like that.
8/18 = 4/9 ( divide both numerator and denominator by 2 )
√4 = 2 and √9 = 3

Answer:
B ) 2/3
This is the table....................