Matrix A is 3x3 whose rows are r1=(0,1,0) & r2=(0,0,1). what is r3 if the...

[Gilligan Island]

...characteristic polynomial of A? abs(A-?I) = -?^3 + 2?^2 + 3? + 7

a) (6,9,21)
b) (14,6,4)
c) (7,3,2)
d) none

Please Explain.