Which part of the circulatory system is responsible for exchanging nutrients and waste

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

Why doesn't heat added to water make the tempature rise above 100c

I'm learning about the periodic tables and what each subject's configuration is. for example, hydrogen is 1s^1, but i don't understand how you get that. can someone me understand how to figure out how to figure this out? sorry if the question makes no sense, but it would really a lot if you could me understand! you so much if you can!