A standard twin mattress is 39 by 75 inches. A king is 76 by 80 inches. This means that a headboard for a king bed is going to be about 76 inches or wider, plenty wide enough to go along the length of a twin bed. Headboards are often slightly wider than the bed for which they are made.
Hemoglobin, Hematocrit, Blood Count. In order to donate blood, a woman must have a hemoglobin level of at least 12.5 g/dL, and a man must have a hemoglobin level of at least 13.0 g/dL. For all donors, the hemoglobin level can be no greater than 20 g/dL.
You should not give blood to get tested for AIDS. Using blood donation as a way to get tested could put the blood supply at risk and endanger patients. HIV antibodies may take a few weeks to develop after infection with the virus. If you were recently infected, you might have a negative test result, yet be able to infect the recipient of your donation. That is why you must not give blood if you are at risk of getting AIDS or other infectious diseases.