Hello,
I believe you're asking which option is true. If so, A) do not require a medium. Unlike mechanical waves, electromagnetic (or light) waves do not require a medium. It has been proven that light travels in a straight line. Light waves are, in fact, electromagnetic radiation, and they can travel in a vacuum.
Faith xoxo
So basically you have to like multiply and stuff so you would freaking get like 250 or something.
Blood platelets... I think are red blood cells, I know we have red and white... hmmm... hope that helps