Thanks for the question! Actually, we know that F and K CANNOT both be photographer’s assistants, based on the second rule. We know that F and K will be trained din different fields, and the two relevant fields are photographer’s assistant and writer’s assistant. So one of them has to be one, and the other one has to be the other. However, we do know that H and J have to both be photographer’s assistants. We’re told about H directly in rule 3. We know that J has to be a photographer’s assistant because G and L are trained in the same field, and we know that H and K/F are photographer’s assistants, so G and L can’t both be photographer’s assistants as well. So G and L are both writing assistant’s, that leaves J left to be the last photographer’s assistant.
Hope this helps. Feel free to ask any further questions that you might have.