Albiote Laboratories has invested in a high-performance centrifuge to treat blood samples received from clinics. In the first step of chemical purification, a technician places test tubes containing the sample in a purifier and adds necessary chemicals; this step takes 3 minutes per sample. In the second step, the same technician loads the sample test tubes in the centrifuge (which can hold up to 5 samples) and adjusts its settings and switches it on. This loading and setting step takes 5 minutes, irrespective of the number of samples placed in the centrifuge. The actual centrifuging step itself takes an additional 25 minutes and does not require the technician to supervise. Assume that the unloading step is instantaneous and clinics send their samples in groups of 5 to the lab. What is the capacity of the process in terms of the number of treated samples per hour?