Nathan collected $15.00 from selling lemonade and fruit punch at a stand in his front yard one day. From his fruit punch sales he collected $9.00. If he charges $0.75 for each cup of lemonade, how many cups of lemonade did he sell that day?​

One card is dealt from a 52 card deck. find the probability that the dealt card is a 4 or a black 7

Consider the function y = f(x)=3^x the values of f(1/2) and f(1/4). rounded to the nearest hundredth, are__and__ respectively

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.