1.) Smoke is coming from the volcano and beneath the surface and it is causing the air to be unbreathable. I think everyon should cover their mouth and nose with a cloth or their shirt while getting to somewhere safe.

2.) Peg didn't want to keep going up the mountain because he sensed that there was something wrong with the air and the mountain was abnormal. There was also dead animals which had no wounds which could make Peg scared. I would react the same since who would really want to go up a active volcano after seeing and smelling smoke in the air as well as rumbling beneath you.

3.) Tata knows that mountains aren't solid rocks and that there are gases, fire and melted rock. He knows this because he had read it in a book Virgil wrote about a mountain in Greece.

4.) When Marcus and Tata try to warn people about the erupting volcano, nobody listens to them as they think that they are just some poor slaves that want to spread misinformation or say this as a joke. But then when the volcano finally erupts, everybody agreed with Tata that they should run as they can see it for themselves.