Tell whether the sequence is arithmetic. if it is what is the common difference?

yes; 5

Step-by-step explanation:

To determine if the sequence is arithmetic, take the second term and subtract the first term

-7 - (-12) = -7+12 = 5

This would be the common difference if our sequence is arithmetic

Now take the second term and add the"common difference"

-7+5 = -2  This is our third term

-2+5 = 3  This is our fourth term

The sequence is arithmetic with a common difference of 5