P2. For isocentric Co-60 treatment, a patient is treated at a depth of 12 cm, field size = 10x10 cm² and SAD = 80 cm. If the tumor receives a dose of 2.5 Gy, find the dose at spleen 4 cm depth. (Use the TAR data) P3. A patient is to be treated using Co-60 machine and a dose of 200 cGy is to be delivered to 10 cm depth. Find the dose at d = 5, 15, and dmax = 0.5 cm given that the SSD = 80 cm and the field size is 15x15 cm2. (You are allowed to use the %DD tables only) P.4 In the previous example suppose the treatment was done from front and back where the dose at d = 10 cm is 100 cGy from the front beam and the same from the back beam. Recalculate the dose at d = 5, 15, and 0.5 cm.