Answer:
the magnitude of the dipole moment is 3.5*10^-11Cm
Step-by-step explanation:
The dipole moment is given by the following formula:

r: distance between the centers of the charges = 500mm
q: charges of the bowling balls = 0.70nC
By replacing you obtain:

hence, the magnitude of the dipole moment is 3.5*10^-11Cm