Answer:
-25/21
Step-by-step explanation:
m=(y2-y1)/(x2-x1)=(15-(-10))/(-15-6)=(15+10)/-21=25/-21
A rational number is a number that can be written in the form:

Where p and q are coprimes. We are asked for finite sets, we can rule out options 3 and 4. In the set in option 2 the first element is:

This number cannot be written a ratio. We can rule out option 2.
All the elements in the set from option 1 can be written in the form p/q.Thus, the answer is the first option.
ANSWER

EXPLANATION
The complex number shown has coordinates (2,-2)
or

The modulus is


The argument is


The polar form is

The first option is correct.