b.

71.

At times, there are two equally simple ways

to describe a plot.

For example, in the

Veitch diagram below, it is evident that

there are no groups of four plotted squares.

There are, however, three distinct groups of

two plotted squares.

This plot can be

described two different ways as follows:

Either of the expressions above is correct.

The number of terms and the variables are

comparable; therefore, the two expressions

are equally simple.

Extract a simplified

expression from the Veitch diagram below.