Not all answers are correct

In Canada, the hydrostatic test for tanks is required every 5 years & not every year as the answer states. Hence, the correct answer should be that it varies from country to country.
Also, when you have pain in your ears on the way down, you should slow down &/or ascend a few feet then try equalizing again; the answer states "equalize" which one does whether you have pain or not.

Regardless, a good way to refresh your dive theory since most of us dont think about it unless were instructors.

GaiJinz about Scuba Exam, v1.0.6