Answer: Fourth option.
Step-by-step explanation:
By definition, a relationship is a function if and only if each input value (or each x-value) has only one output value (or y-value).
Given the first table:

You can notice that the input values 2 and 3 do not have only one output value. Therefore, this table does not represent a function.
The second table is:

You can notice that the input values 4 and -4 do not have only one output value. Therefore, this table does not represent a function.
The third table is:

You can notice that the input values 6 and 7 do not have only one output value. Therefore, this table does not represent a function.
The fourth table is:

You can notice that each input value has only one output value. Therefore, this table represents a function.
Answer:
m <PRQ is 15 degrees.
Step-by-step explanation:
For this equation I would assume you use substitution, you plug in what y equals (3x -2), for the y in the second equation (4x - 4y = 8), you now have 4x - 4(3x-2) = -8 you then proceed to factor out this equation, you distribute the -4 and now you have 4x -12x + 8 = -8 you then subtract the -12x from the 4x and the result is -8x + 8 = -8, you then proceed to isolate the x subtracting the 8 from both sides and you now have -8x =-16 you then isolate the x by dividing -8 from both sides, your results are x = 2, you answer isn’t negative 2 because when you divide two negatives they cancel out creating a positive number.
Very easy the answer is 20