Answer:
A is the closest answer, My answer would be: Make sure everyone is focused and heard or included.
Explanation:
A. To introduce information for the group to discuss? Yes, This is very important, you are now firstly, getting everyone on track on what to do, and second, make sure to have everyone included
B. To help resolve conflicts during group discussions? Important but not really.
C. To take notes on the main points of discussion? again, Important but not really.
D. to track the time spent on the group discussion? That sounds like a minor job that a leader shouldn't do.
The sentence "Moreover, it is probably just as valuable or more valuable to us now, than it was in the ancient past".
Answer:
1)

2) slope is -2/3
Explanation:
1)

2)
when any equation is written as
y = mx + c then m is the slope.
above we have calculated that

which is in the form of
y = mx + c
where m is -2/3 and c is -6
thus slope is m = -2/3
Answer:
Bullion is money, specifically gold or silver that has been freshly mined but not cleaned and made into money.
Clues to the meaning include the fact that the kids need "3 dollars", the speaker doesn't know how they wanted all that "money" at one time, and they had to "raise" it, as in "raising money". When he says, "I hadn't any idea where to turn to raise all that bullion..." he means the 3 dollars.