What do red blood cells carry?

Which of the following particles always has a positive charge? a. electronb. neutron c. proton d. ion

Drag each description to the correct location on the image. not all descriptions will be used. describe the parts of a comet. the frozen part of the comet the atmosphere of gases and dust formed when the nucleus vaporizes tail made of small, solid dust particles tail made of ions that appears to point away from the comet's orbit

How energy flows through each level in this energy pyramid. is all the matter and energy from one level transferred to the next level?