In a double-replacement reaction: one of the products is always a gas. one of the products must be an element. positive ions are exchanged between two compounds. all of the above

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.

Which of the following characteristics are true of enzymes? check all that apply. a.)the structure of an enzyme can change if conditions change. b.)a single enzyme can normally catalyze a wide variety of reactions under many conditions. c.)enzymes are found only in nonliving systems. d.)enzymes allow living things to regulate body conditions through feedback mechanisms. e.)enzymes bind to specific substrates in specific ways. f.)enzymes increase the rate of reaction. g.)when shown in energy-reaction diagrams, enzymes represent the higher activation energy.

The smallest species of chameleon is found only on an island in madagascar the island has unique geological and climatic conditions that are essential for the chamaeleon to survive the chamaeleon was recently declared an endangered species years from now why won’t this chameleons remains make for a good index fossil