If x−y=3 and x+y=5, what is the value of y?

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Astudent survey asked: "how tall are you (in inches)? " here's the data: 67, 72, 73, 60, 65, 86, 72, 69, 74 give the five number summary. a. median: 73, mean: 70.89, iqr: 5, min: 60, max: 74 b. 60, 66, 72, 73.5, 86 c. 60, 67, 72, 73, 74 d. 0, 60, 70, 89, 74, 100

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.)