Answer the questions on the basis of the information given below.

Twenty one participants from four continents (Africa, Americas, Australasia, and Europe) attended a United Nations conference. Each participant was an expert in one of four fields, labour, health, population studies, and refugee relocation. The following five facts about the participants are given.

1. The number of labour experts in the camp was exactly half the number of experts in each of the three other categories.
2. Africa did not send any labour expert. Otherwise, every continent, including Africa, sent at least one expert for each category.
3. None of the continents sent more than three experts in any category.
4. If there had been one less Australasian expert, then the Americas would have had twice as many experts as each of the other continents.
5. Mike and Alfanso are leading experts of population studies who attended the conference. They are from Australasia.