(6.03 mc)ecotourism can provide an incentive for local people to preserve the environment in order to attract more visitors, but sometimes development is done with little planning for long-term environmental impacts. on a small island in the caribbean, a local group is considering opening a resort for ecotourism. if they wish to build a sustainable and ecofriendly business, what should be the next steps in their plan?
a. investigate the ecological impacts and gather evidence on which to base their decisions
b. hire an agent to locate a suitable property and start developing infrastructure
c. market the development to investors and explain ecotourism to them to raise money for the resort
d. determine what types of activities the resort will offer and hire staff

For a comparative or experimental investigation, scientists often make a testable about a scientific question, and then they test it in the investigation. a. control b. hypothesis c. procedure d. system

To answer this question, researchers studied populations of the dusky salamander (desmognathus ochrophaeus) living on different mountain ranges in the southern appalachian mountains. the researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. four mating combinations were tested for each pair of populations (a and b)—two within the same population (female a with male a and female b with male b) and two between populations (female a with male b and female b with male a). the proportion of successful matings for each mating combination was measured. for example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). the reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (aa + bb) minus the sum of the proportion of successful matings of each type between populations (ab + ba). the table provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.

Which greenhouse gas is emitted when burn fossil fuels for energy? a. nitrogen b. oxygen c. carbon dioxide d. helium