The half-life of Strontium-90 is 28.8 years. how long will it take for 3/4 of a sample of Strontium-90 to decay? (you can include work but u don’t have to)

The human activities in two locations are described below: location a: rampant use of plastic containers location b: excessive use of pesticides and fertilizers which statement is most likely true? location a will have poor air quality because plastic is biodegradable. location a will experience water scarcity because plastic absorbs moisture. the population of honeybees will increase in location b because production of crops will increase. the population of fish in location b will decrease because the water is contaminated.