Answer:
1st: Linear
2nd: Exponential
3rd: Neither
Explanation:
See the attached graph.
The first data set is linear. The line y = -5x + 21 matches the points.
The second data set is exponential. The points don't quite match the equation of 0.5x^2, but the similarity in shape can be observed.
The third data set is neither. Although the line y = x - 1 comes close (matches 4 of the 5 points), the value (1/2) does not fall on the line.