1: If you decided to try the Root test, you should have done the following calculation:
How does it compare to 1?
If you decided to try the Ratio test, you should have done the following calculation:
How does it compare to 1?
If you decided to try the Integral test, the first thing to do would be to check that the appropriate function is decreasing on some suitable neighborhood of infinity.
Using integration by parts and improper integral you should have calculated
Now make your conclusion.