A paper mill releases foul-smelling smoke, lowering nearby homeowners' property values without compensating them. What spillover occurs?

A student receives a flu vaccination, reducing the chance that classmates will catch the flu. What spillover results?

A beekeeper's hives pollinate a neighboring apple orchard, increasing the orchard's harvest. The orchard pays nothing to the beekeeper. This is what kind of externality?

A concert venue's late-night noise prevents nearby residents from sleeping. The residents are not compensated. How should this effect be classified?

A business plants and maintains a flower garden along its storefront, making the whole block more attractive to passersby. What spillover is created?

One homeowner installs bright security lighting that also discourages crime on neighboring properties. The neighbors did not help pay. What is this effect?

A tanker leaks oil into a bay, reducing the catch of independent fishers who did not cause the leak. What kind of spillover do the fishers experience?

A good is nonexcludable when people cannot easily be prevented from using it, and nonrival when one person's use does not reduce others' use. What kind of good has both traits?

A town considers building a seawall. Once built, it protects every coastal home, including homes whose owners did not contribute. Why might private markets underprovide it?

A city fireworks display can be watched by residents who did not buy tickets, and one more viewer does not reduce anyone else's viewing. Why is it a public-good problem?

A neighborhood has no streetlights because each household hopes another household will pay for them, even though all would benefit. Why can the market provide too few streetlights?

A county's tornado-warning siren alerts every resident within hearing range, whether or not that resident paid for it. What characteristic helps explain government provision?

A private company will not fund mosquito-control spraying because all nearby households benefit even if only some pay. What market problem is described?

A coal plant's electricity price does not include the health costs of its sulfur dioxide emissions. Which policy best makes the plant account for this external cost?

A state wants more households to install insulation because reduced energy use lowers air pollution for everyone. Which government tool best encourages this positive externality?

A factory dumps chemicals into a river, harming downstream drinking-water users. Which government action most directly limits this negative externality?

Residents want streetlights on a public road, but no business will build enough because it cannot collect payment from all users. What is the most fitting government response?

Two dominant local cable companies propose merging, and the merger would leave consumers with far fewer choices. Which government tool addresses this problem?

Too many boats harvest fish from an open-access lake because each boat ignores how its catch reduces fish available to others. Which policy can help manage this shared resource?

A landlord hides serious mold problems before renting apartments because prospective tenants cannot easily inspect inside the walls. Which response best addresses this information problem?

A buyer and seller disagree after a signed contract is not fulfilled. A court applies contract law and orders a remedy. Which government role is illustrated?

The Federal Trade Commission sues to stop rival companies from secretly agreeing on the prices they charge. What government role does this represent?

The Environmental Protection Agency enforces limits on certain air pollutants from regulated sources. Which role of government is this?

Social Security provides monthly benefits to eligible retired workers. Which government role is most directly shown?

A state transportation department builds and maintains a bridge that any driver may use without paying at the crossing. Which government role is best illustrated?