Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Paper format. 98-Phys-B1 Radiation Physics, National Examination May 2016 — a three-hour open-book examination in which any non-communicating calculator is permitted (the candidate must record the calculator's make and model on the first sheet). The cover page states the exam has 7 questions worth a total of 89 points, of which only 80 points' worth need be answered for full marks; every question and sub-part is nonetheless answered in full below so the paper remains a complete study resource. The cover page's own marking-scheme summary (12+5+10+6+16+20+20 = 89) is internally consistent with the stated total. The cover page also invites the candidate to submit a written statement of any assumptions made where a question is open to interpretation — this licence is used below in Question 2 (the source unit "pGy" is used literally though it is almost certainly a truncated "mGy"/ "μGy"; the ratio of contributions, which is what the question asks for, is unit-independent), Question 5(b) (the fission-energy-distribution percentages are illustrative textbook values, since the source gives no numeric data to compute them from), and Question 6 (the "dots" in the count-rate table are filled in via Poisson counting statistics and the stated variance combination rule).
Reference texts. K. S. Krane, Introductory Nuclear Physics (nuclear reaction equations, fission energetics, mass–energy conservation); F. H. Attix, Introduction to Radiological Physics and Radiation Dosimetry (photon interactions, pair production, attenuation); J. R. Cember and T. E. Johnson, Introduction to Health Physics, 5th ed. (internal dosimetry, radiation weighting factors, ALARA/protection tenets, counting statistics); J. E. Turner, Atoms, Radiation, and Radiation Protection, 3rd ed. (tritium hazards, neutron interactions, non-ionizing vs. ionizing radiation).
