He used the lense to concentrate the sunlight, in effect as a "burning glass."
A: Because Ralph blew it and he was the "adult" of the group.
B: They enjoyed the entertainment of the assemblies.
Robert Gets Hurt when the Boys Pretend he is a Boar.
Piggy suggest that Ralph use the conch shell for authority, the right to speak..
When Ralph chose Simon and Jack to accompany him on his expedition to climb the mountain Piggy asked if he could come to. He was disappointed when Ralph refused his offer. He also expressed his disappointment that Ralph had revealed his nickname to the other boys despite Piggy earlier asking him not to do so.
Jack and his hunters try two strategies. Jack first had a boulder from the top of castle rock sent crashing into the thicket with the intention of either killing Ralph or driving him out of hiding. When this failed Jack then lit a fire, hoping to smoke Ralph out of the thicket.
Piggy's glasses were used as a burning glass by Ralph to light the fire.
The boys were travelling on a plane. The "passenger tube" of this plane was ejected during a storm because the plane was attacked. The "passenger tube" then crash landed on the island but was soon dragged out to sea by the storm, with many of the boys still on board.
Physically Jack is described as being, and I quote... "He was tall, thin, and bony: and his hair was red beneath the black cap. His face was crumpled and freckled, and ugly without silliness. Out of his face stared two light blue eyes, frustrated now, and turning, or ready to turn, to anger." Piggy was intimidated by Jack's superiority and offhand authority. Jack is also described as being 'one who knew his own mind' and as speaking with simple arrogance.
He gives up on his hope for getting rescued.
Although we are not told what school the boys come from, we can presume that they had attended different schools because of the fact that, with the exception of the choir, the boys do not know each other before the events on the island. We can back this up as Piggy is initially given the job of "taking names", and because all of the boys feel the need to introduce themselves during the first meeting.
Piggy goes to castle rock with the intention of demanding the return of his stolen glasses. When he is standing on the causeway he makes a speech. His obvious intention is to try and persuade the boys that it is better to act sensibly and try to get rescued than to behave like savages. Unfortunately Piggy fails to appreciate how far removed from civilised behaviour Jack's tribe have become. As a sort of miniature adult Piggy has no understanding of how the minds of boys work. He speaks to Jack's tribe as if he were an elderly school master chastising a class full of naughty schoolboys. This simply infuriates the boys, who probably see themselves as brave savages and hunters. They object to be lectured to by a fat boy who they don't even like, let alone respect.
Fire and more importantly Piggy's glasses. I guess you could also include Sam n Eric who Jack's group "capture" and force to join their tribe.
Lord of the Flies ends with the arrival of the naval officer and his crew on the island. This indicates that the boys will be rescued and Ralph is saved from certain death at the hands of Jack and his hunters. The resolution is that the uncomplicated and happy boy at the start of the book has been transformed through his experiences into a traumatised boy who weeps for the death of his friend, the loss of his own innocence and the darkness which he know lies in the hearts of all men.
Maurice and Roger show their power by throwing rocks at the littluns playing with the sand castle, but Maurice's conscience tells him that it is wrong, so he feels ashamed at the end. This symbolizes that Maurice still has a bit of human civilization in him. Roger on the other hand seems to be the most evil of all the boys. He is the boy that kills Piggy and he seems to want power a lot. He throws rocks at the littluns and he is Jack's right hand man. Near the end of the book, when they take Samneric captive, Roger does something bad to them to make them go into Jack's group. Roger is described as being quiet, and he observe everything going on around him with close attention. So basically Maurice and Roger show their power by being forceful and violent.
Yes, it is based on a real plane crash during the world war where boys lived on an island and only a few ever survived.