The second question asks for exactly the opposite of the first question. We need minimum overlap of the three regions (name, fax and telephone number)

1) Database E= Total Entries= Using line technique, we will try drawing lines in such a way that the overlap is minimized as follows

$\begin{array}{ccc}\text{Name}& \text{Fax Number}& \text{Telephone Number}\\ 100& 50& 80\end{array}$

Thus, the region of minimum overlap of 3 lines is 30% of 15000 = 4500. Option (c)

To visualize this using venn diagrams, see below

Line technique is an alternative and better representation of sets where there is no upper limit to the details which need to be compared.