Write and solve a system of three equations with three unknowns to solve the given word problem. In Juan's coin bank there are nickels (n), dimes (d), and quarters (q). The number of quarters is one-quarter the number of dimes, and the number of nickels is twice the number of quarters. The total value of the coins is $6.00. Find the number of each type of coin.
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You drop a rubber ball off the roof of a 50 meter high building onto a paved parking lot. it bounces back up with every bounce, but not quite all the way back up to you. after the first bounce it bounces back only 80 percent of the distance it was dropped from. the pattern continues, meaning after every bounce it comes up to just 80 percent of the previous maximum height. so if before the first bounce the height is 50 meters, what height does the ball reach after the fifth bounce? round your answer to one decimal place and chose the correct response from the choices below:

Give all possible names for the line shown. calculation tip: lines can be written with either point first.

Which part of a 2-column proof is the hypothesis of the conjecture? a) given b) reasons c) prove d) statements ! i think it's b but i'm not quite