Aclient is undergoing photochemotherapy involving a combination of a photosensitizing chemical and ultraviolet light. what health problem does this client most likely have?

Psoriasis is a skin disease that manifests itself in symptoms of varying severity. It is a chronic disease that can not be cured but can be alleviated by many treatments (like chemotherapy).
Photochemotherapy: also called P-UVA. It consists of the combination of UVA (a type of UV light) radiation after the local or oral administration of a psoralen that acts as a sensitizing photo. It is used alternately in patients for whom UVB (another type of UV) has no effect, as P-UVA is more effective and longer-lasting, but is associated with basiloma (basal cell carcinoma) and melanoma.

The answer is joseph is observing the colour of the reaction mixture to see whether proteins are present in the given solution.

Well, both latitude and intensity of light affect temperature because, the higher the light intensity, the higher the temperature and since latitude is the measure of how close you are to the equator, then the closer to the equator you are, the higher the temperature is.