(a) Diameter of the sphere, d = 2.4 m
Radius of the sphere, r = 1.2 m
Surface charge density, = 80.0 μC/m2 = 80 × 10−6 C/m2
Total charge on the surface of the sphere,
Q = Charge density × Surface area

Therefore, the charge on the sphere is 1.447 × 10−3 C.
(b) Total electric flux (ϕTotal ) leaving out the surface of a sphere containing net charge Q is given by the relation,
ϕTotal =Q/εo
Where,
εo= Permittivity of free space
= 8.854 × 10−12 N−1C2 m−2
Q = 1.447 × 10−3 C
∴ϕTotal=(1.447×10−3) /(8.854×10−12)
= 1.63 × 108 N C−1 m2
Therefore, the total electric flux leaving the surface of the sphere is 1.63 × 108 N C−1 m2.