Sodium and are the two primary electrolytes. question 5 options:
iron
potassium
zinc
iodine

altitude, density, pressure

air gets less dense the higher the altitude and also the air pressure is less as altitude rises.

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

i think? ?