You breathe in more oxygen than you breathe out. and you breathe out more carbon dioxide than you breathe in. what type of change is oxygen turning into carbon dioxide? a. physical only b. chemical only c. physical and chemical

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping

Which of the following is true? a. under the current unemployment insurance system, benefits replace about 90 percent of the typical worker's prior pretax earnings. b. high benefit payments to unemployed workers will tend to increase the rate of unemployment. c. if a system of personal savings accounts replaced the current unemployment benefit system, the unemployment rate would fall to zero. d. the rate of unemployment in the large european economies has been persistently lower than that of the united states due to their more generous unemployment benefits.