Why did the author choose the problem-and-solution structure?

After rain, water soaks into the ground and is added to the groundwater. this process is known as a. groundwater pollution. b. groundwater recharge. c. groundwater recycling. d. groundwater filtration.

Of the 168 hours in a week as a full time student you should spend how many hours per week on school work?

Alaser tag arena sells two types of memberships. one package costs $325 for one year of membership with an unlimited number of visits. the second package has $125 enrollment fee, includes five free visits, and costs and additional $8 per visit after the first five. how many visits would a person need to use for each type of membership to cost the same amount over a one-year period?