A street noodle vendor (one server) in Singapore can service an average of 20 customers per hour. Given an average arrival rate of 12 customers per hour, calculate the mean waiting time in the system (being served and in the queue). Group of answer choices 4.5 minutes 2.5 minutes 1.5 minutes 3.5 minutes 7.5 minutes

Amachine purchased three years ago for $720,000 has a current book value using straight-line depreciation of $400,000: its operating expenses are $60,000 per year. a replacement machine would cost $480,000, have a useful life of nine years, and would require $26,000 per year in operating expenses. it has an expected salvage value of $130,000 after nine years. the current disposal value of the old machine is $170,000: if it is kept 9 more years, its residual value would be $20,000. calculate the total costs in keeping the old machine and purchase a new machine. should the old machine be replaced?

How did the contribution of the goods producing sector to gdp growth change between 2010 and 2011 a. it fell by 0.3%. b. it fell by 2.3%. c. it rose by 2.3%. d. it rose by 0.6%. the answer is b

Your dormitory, griffingate, has appointed you central banker of its economy, which deals in the currency of wizcoins. assume that the velocity of wizcoins in griffingate is constant at 10,000 transactions per year. right now, real gdp is 1,000 wizcoins, and there are 2,000 wizcoins in existence.