Answer:
<h3>80.1 x 10 <em>7</em></h3>
Step-by-step explanation:
The domain is the set of possible inputs, i.e. the x-coordinates of the points.
Here those are 6, 1 and - 3 which in order is -3, 1, 6.
Then the answer is {-3, 1, 6}.
By the way note that this relation is not a function. Do you know why?
Because the image of -3 is not stated unambiguosly.
We are to form the combination of 6 objects taken 2 at a time. This can be expressed as 6C2

This means, there can be 15 different combinations of 2 members that can sit in the front row.
So, the answer to this question is option A