1.) The name of the main character is Marcus
2.) There was going to be more work for Marcus and the other slaves because their Master, Festus Julius, was inviting guests over to have a feast. In order to impress his friends, Festus forces the slaves to make sure the palace was extra clean and was perfect, otherwise the slaves would most likely get punished.
3.) The old lady warns Marcus about the doom of Pompeii and tells him, "When hope is lost, follow the hand of Mercury." This old lady is trying to tell Marcus that in the future, during the eruption of Vesuvius(Marcus doesn't know this), they will have to go to where the hand of Mercury points and uncover the secret passageway that leads them out of the city.
4.) When Marcus sees Tata dressed in armour and in the line of the gladiator parade, he realizes that his father was going to be sent in the arena to fight for his life. Knowing that his dad will most likely die in the battles, he tries to find a solution to get him out of fighting. His solution to this was ingenius and it involved disguising himself as a son of a rich person by wrapping Festus' toga around him. He then grabbed a basket with a giant snake and ran toward the parade, then dumping the snake onto the lanista which scared all the guards to run away. This finally gave Marcus and Tata the opportunity to run away and climb the mountain.