PLEASE HELP! A sample of radioactive waste will have reached an acceptable activity level at 0.5 curies . If the half - life of the sample is 5 years and the sample can be disposed of after a minimum of 20 years , what must the original activity level of the sample be ?

For the strategies below, decide whether they are best described as demand-side solutions or supply-side solutions to meeting human needs for fresh water. remember that a demand-side solution reduces demand for fresh water, whereas a supply-side solution increases the supply of fresh water. (a) damming a river to create a reservoir (b) desalinating seawater (c) a nation invading a neighboring country to access their rivers (d) raising water prices for consumers and businesses (e) providing tax breaks for companies that use less water (f) replacing inefficient irrigation with more-efficient drip irrigation to grow crops (g) requiring low-flow showerheads in all new homes