Answer:
(A) Capacitance per unit length = 
(B) The magnitude of charge on both conductor is
C and the sign of charge on inner conductor is
and the sign on outer conductor is 
Explanation:
Given :
Radius of inner part of conductor
=
m
Radius of outer part of conductor
=
m
The length of the capacitor
=
m
(A)
Capacitance is purely geometrical property. It depends only on length, radius of conductor.
From the formula of cylindrical capacitor,

Where, 
But we need capacitance per unit length so,

capacitance per unit length =
(B)
The charge on both conductors is given by,

Where, C = capacitance of cylindrical capacitor and value of
F,
V
∴
C
The magnitude of charge on both conductor is same as above but the sign of charge is different.
Charge on inner conductor is
and Charge on outer conductor is
.