hel. which of the following statements regarding physical and chemical changes is true? a. both physical and chemical changes alter the atomic structure of a substance. b. neither physical not chemical changes alter the atomic structure of a substance. c. physical changes alter the atomic structure of a substance, while chemical changes do not. d. chemical alter the atomic structure of a substance, while physical changes do not. hur

According to the tide table below what time of day will the highest tide occur? (2 pt) the highest tide will occur at

What effect would average population growth have on land usage? a. urban use of land would rise to more than 30 percent of available land. b. industrial use of land would rise to more than 30 percent of available land. c. the percentage of available land used as cropland would stay the same. d. cropland would fall to about 10 percent of available land.

Air pressure is measured in pascals. for a professional american football game, the ball should be inflated to about 90,000 pascals. scientists studied the effects of air temperature on the pressure inside american footballs by taking these steps: 1. prepare 100 footballs. 2. measure each football's air pressure. 3. divide footballs into 10 groups. 4. place the groups in different lockers cooled to different air temperatures. 5. after 12 hours, remove the footballs from lockers. 6. measure each football's pressure again. 7. compare the new pressures to the starting pressures. what two terms best describe the variable "air pressure inside the football" in this experiment? independent, qualitative independent, quantitative dependent, qualitative dependent, quantitative