This is just like the last one can anyone help I’m confused?!?

Which of the following systems in absorbing oxygen and releases carbon dioxide

What is true of all organisms in the kingdoms protista, plantae, fungi, and animalia? a. they are multi-celled. b. they are photosynthetic. c. they have cells that contain membrane-bound organelles. d. they contain cells that lack membrane-bound organelles.

Im inn a ! what"s the answer which of the following is one way creativity can scientists? by ensuring they follow the scientific method by increasing the amount of time it takes to complete scientific experiments by making sure they only try things that have already been proven by leading them to ask more questions about the natural world