uhmm it is... not really hard i guess
for q 29 a (i) i guess you just explain how the radioisotopes used to identify, you say that is chemically attached to molecule that take part in the biochemistry of the body and say that it can produce the structure and functioning and you can also say that radioisotope produce positron antrimatter of electron and when they collide they annihilate producing 2 gamma rays that can be detected by the computer and the computer will for the graph. moreover you can say that PET can be used to trace a metabolic change so it can confirm the correction made
ii just say 99TC for it is technetium 99 and that is the most widely used in medical physic (if you read the PET scan in internet) why? because it get shor half life and since it is emitting gamme, it is suitable because the short half life enables the PET to confirm the correction for 6.02 hours eq the patient will never be corrected for 20.30 minutes isnt it? and don't ever justify that you will do twice PET scan, since the scan is expensive, and you can also say it is non alpha emitter
b (i) just calculate it, and remember you can eliminate 10^6 since it is just the same amoung as the Z2 and Z1
ii just compare it, the x-ray uses cathode rays, fast moving electrons suddenly stopped by the high atomic number and somehow you can further says that the x-rays is get accelerated with more high speed to make the kinetic energy get transferred to heat at a single collision to make the softer x-rays becomes harder x-rays
for the endoscope you can say that it uses the TIR (total internal reflection) and using the snell's law
(c) just explains what is a-scan, b-scan(sector scan) and phase scan.. and you must explain the advances of each scanning system e.g. you could say in a-scan the transducer is stationary and it also measure distance or depth, but in b-scan the transduer is circling around a sector or moved backward or forward to get different spot with different intensity to form 2 dimensional images and the phase scan uses the phase array transducer that allow a real time image to be captured... for the current issues you can just explain that more abortion since some cultural fact that states some people would prefer boys/girls or if they know the baby is twin they would do abortion
d(i) this is very easy since the superconducting magnet is used to exert magnetic field to the atomic nuclei to make it in the two states antiparallel and paraller and the magnetic also produces the lamour precession and lamour frequency and Radio frequency you can justify it by saying that it is used to detect the signal, why? because if we supplied the radio frequency equal to lamour frequency the magnet will turn to spin down state and when we cut it off the spin down magnets get back to its state give up the same energy frequency that is given and this frequency allows the signals to get detected
q29 ii Gadolinium,, you can say that is has increased the signals or the amount of proton in the atomic nuclei
iii quite tough one, but it is clearly known that CAT is more invasive and MRI is non invasive because CAT uses x-ray that is ionizing radiation that can knock off electron in the atom and creates ion, this ion can cause the DNA break down or mutate to becomes cancerous cells, you may say that MRI is good at give the detail of the image of soft tissues rather than CAT because MRI can detect the watery organ of the body, MRI can get clear image of the internal organ, and the last you could say that it can prevent further cost of medical and extensive surgery
it is not hard actually but i guess it is not easy tooo