Birds that fly have lightweight bones some of which are hollow how might this unique body structure benefit the bird?

Two critical interventions to turn around the opioid crises are:

To test the responsiveness of the kidneys, scientists have designed an experiment tracking urine output of people during a normal day, while regulating the in-take of water by mouth. what would be an appropriate hypothesis for this experiment?

Which promotes sustainability? o a. using more landfills o b. finding new sources of coal o c. increasing consumption o d. encouraging recycling programs