What do the bands in positions A-F represent in EMSA?

What does the number 18.9984 represent in the image?

Red blood cells are responsible for transporting oxygen in the blood. people with sickle cell anemia were born with a defective gene that results in sickle-shaped red blood cells. individuals with the disease often suffer pain in their extremities due to the build-up of these cells causing blockages in the blood vessels. the shape of the blood cells also reduces the amount of oxygen transported in the blood.

Kidney stones are tiny crystals of calcium or magnesium that block the narrow sections of the excretory system. which symptoms would a person with kidney stones experience? a. inability to store urine; pain in the bladder b. inability to store urine; pain in the urethra c. reduced urine flow; pain in the bladder d. reduced urine flow; pain in the urethra