please write equations with full explanation

course is medical imaging.

3. (a) What determines the highest energy of x-ray photons emitted from an x-ray tube? (b) In x-ray imaging for medical applications, why are low-energy photons undesired? What measures can be taken to reduce the number of low-energy photons entering the human body? (c) why are photons undergoing scattering undesired? What measures can be taken to prevent these photons form entering the detectors