A plane area of 100 cm² is placed in a uniform electric field of 100 N/C such that the angle between the area vector and an electric field is 60^o. The electric flux over the surface is:

The electric field cannot flow on itself, electric flux is the measurement of the electric field via a certain surface. 
It is a technique of expressing how strong an electric field is at any distance from the charge that is producing it.
The electric flux is calculated as the sum of the area and the electric field.
Electric Flux 

$\mathrm{\Phi }=\mathrm{E}.\mathrm{A}=\mathrm{EAcos\theta }$

$\Rightarrow$$\mathrm{\Phi }=0.01 {\mathrm{m}}^2\times 100 \mathrm{N}/\mathrm{C}\times \cos 60°$

$\Rightarrow \mathrm{\Phi }=0.5 \mathrm{Wb}$