Interval notation is very easy. It is just asking you for the interval of x where f(x) is increasing/decreasing/positive y/negative y.
Now you look at your graph and let's say the graph increases, meaning y gets bigger as x gets bigger, between 2 and 5. The interval form would be [2,5] if both ends are included. If 2 was not included you would just put ]2,5]. Do the same for the other questions.