A good answer might be:

Of course. Bit patterns can represent anything symbolic.

Bit Patterns

The question is silly. There is nothing mysterious about representing signed numbers with bit patterns. Here is another silly question:

Is it possible to represent a fraction with a whole number of bits?

Of course. It is just a matter of picking a bit pattern for each fraction you wish to represent. There are several systematic ways to do this. This chapter discusses some of them.

QUESTION 2:

In the decimal fraction 12.6 what power of 10 is associated with: