Element X is a radioactive isotope such that every 91 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 80 grams, how long would it
be until the mass of the sample reached 68 grams, to the nearest tenth of a year?

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

Empty box + box + empty box fill in the box is equal to 30 how

The krasnapolski is a top-of-the-line hotel in amsterdam, the netherlands. among their many services, they rent bicycles to guests. the bicycle checkout is open 24 hours per day 7 days per week and has 50 bicycles on hand. on average, 10 guests request a bicycle each day, arriving completely randomly at all times of the day during the spring and summer seasons. guests keep bicycles for four days on average, with a standard deviation of two days. how long does a guest on average have to wait for a bike? a. approximately 24 hours b. approximately 0.033 hours c. approximately 4 days d. approximately 47 minutes