Ineeed hlpp im not sure wich one it is

A) because the decimal is repeating, 625.49 is irrational.
B) because 625.89 can be written as the ratio of two integers, 62589 and 100000, this is a rational number.
C) sqrt(90) can be factored:  sqrt(9)*sqrt(10).  sqrt(9) = 3 (rational), but sqrt(10) is irrational.  Thus sqrt(90) is irrational.
D)  You try this one yourself, OK?

With a continuous thought process.