1 and 2 are a) and c) respectively.
As for 3 I believe it is a) but you may wish to do a little more research on that one.
Answer: unite the colonists in support of continuing the fight for independence
Explanation:
Here's the excerpt:
"I call not upon a few but upon all—not on this state or that state, but on every state—up and help us. . . . Let it be told to the future world that in the depth of winter, when nothing but hope and virtue could survive, that the city and the country, alarmed at one common danger, came forth to meet and repulse it."
The purpose of Paine in issuing this plea is to unite the colonists in support of continuing the fight for independence.
This can be seen in the excerpt as it was inferred that everyone was called to come together and help and repulse the fight for their independence.
Technology allows students to help each other and work together across to better understand the material. In that sense, they can sometimes serve as the (supervised) teachers — and learning through instruction is known to be highly effective for mastering a topic and solving problems.