FLUS& FIELD

charges Q1 &Q2 lies inside & outside respectively of a closed surface S.Let E be the field at any point on S &φ be flux of E over S
a)if Q1 changes ,bothE& φ will change
b)if Q2 changes ,E will change but φ will not change
c)if Q1=0& q2≠0 then E ≠0 but φ =0
d)if Q1≠0 & Q2≠0 then E=0 but φ ≠0
ans ABC