Step-by-step explanation:
The given data is as follows.
Potential (V) =

Distance (r) = 15.6 m
Let us assume that q is the magnitude of charge. Formula to calculate charge will be as follows.
V =

q =

=
C
As the potential due to charge is positive. Therefore, q is positive.
Thus, we can conclude that the sign of charge is positive and magnitude of the charge is
C.