Evaluate the given integral by changing to polar coordinates. r (4x − y) da, where r is the region in the first quadrant enclosed by the circle x2 + y2 = 16 and the lines x = 0 and y = x

Adoctor administers a drug to a 38-kg patient, using a dosage formula of 50 mg/kg/day. assume that the drug is available in a 100 mg per 5 ml suspension or in 500 mg tablets. a. how many tablets should a 38-kg patient take every four hours? b. the suspension with a drop factor of 10 ggt/ml delivers the drug intravenously to the patient over a twelve-hour period. what flow rate should be used in units of ggt/hr? a. the patient should take nothing pills every four hours. (type an integer or decimal rounded to the nearest hundredth as needed.)

You have 37 coins that are nickels, dimes, and pennies. the total value of the coins is $1.55. there are twice as many pennies as dimes. find the number of each type of coin in the bank.

Simplify each expression for 18, 20, and 21