Petrol or gasoline.
"Available" to whom? On what scale?For people with a legitimate use for it, dynamite is pretty easy to get.
No. Ammonium nitrate, combined with a fuel such as #2 diesel oil is the most commonly used explosive in the world today. We use roughly 5 million pounds of that each day, worldwide.
Explosive volcanoes are most common at subduction zones.
Mount St. Helens is generally regarded as an explosive volcano, but like most stratovolcanoes, it can produce both explosive and non-explosive eruptions.
No. The most explosive variety of volcanic activity would be the caldera-forming eruptions of stratovolcanoes. Cinder cone eruptions are only mildly explosive.
Volcanoes with more viscosity are more explosive.
No. Volcanic eruptions in Hawaii are not usually explosive.
napalm
Large explosive eruptions are generally characteristic of stratovolcanoes.
From what I know you can't on any gun other than the MG4 but I may be wrong but I'm CERTAIN explosive rounds are available for the MG4 (:
Most explosive volcanism is located at oceanic to continental subduction zones.
Generally not. Explosive eruptions may happen occasionally, but most eruptions are effusive.