**Concept: **The question tests on the basic understanding in Algebra.

**St(1):-** Only gives information about r and nothing

**St(2):-**R can be +2 or a -2 and then the distance from t would be 4 which is r^2 (=>multiple values of t for same statement=>

**Insufficient)**

**Combining both,**

|r-t| = r^2

=> r-t = r^2 or r-t =

**- (r^2)****=>t = r - r^2 or t = r + (r^2)**

lets take r = -1/2

=> r^2 = 1/4

=>

**t = (-1/2) - (1/4) = -(3/4) or t = (-1/2) + (1/4) = -(1/4)****(Sufficient)**

**(option c)**