Final answer:
The blood sample in a glass tube clots, separating into serum and a solid clot. When both wells with anti-A and anti-B antibodies visibly agglutinate, it indicates the blood type is AB.
Step-by-step explanation:
When a blood sample is collected in a glass tube, the blood starts to clot. During the hour that the sample was in the glass tube, the clotting process occurs and separates the blood into two components: serum and a solid clot. The technician collects the serum for further blood analysis.
In the second scenario, the technician has not made an error. When both blood samples visibly agglutinate after adding anti-A and anti-B antibodies, it indicates that the patient's blood type is AB. The blood type AB reacts positively with both anti-A and anti-B antibodies, resulting in agglutination in both wells.