Which two statements describe organ systems working together to remove wastes from the body? A. The digestive system breaks down food into molecules that can move into the blood. B. The circulatory system carries oxygen-rich blood into muscles in the legs. C. The respiratory system exhales carbon dioxide that enters the lungs from blood vessels. D. The integumentary system gives off thermal energy that comes from blood vessels. ​

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

If an area has high air pressure and low humidity, what type of weather will it most likely have? plz !

Estimate the molar mass of the gas that effuses at 1.6 times the effusion rate of carbon dioxide.