How is wave length measured

How did the discovery of the rhesus factor affect society? o more patients died from having a transfusion with the wrong rhesus factor 0 new treatments during pregnancy could prevent harm to the developing child. o less donated blood could be used in the treatment of patients. the number of blood types was reduced by half

Plsss > .< compare and contrast the characteristics of flatworms rounds worms and earthworms

What in scientific term why the salty popcorn causes this thirst