public BigDecimal getStudentExpenses(Student s) {
		BigDecimal amount = new BigDecimal(0.0);
		// 1º Get activities prize
		Set<Activity> activities = s.getActivities();
		for (Activity a : activities) {
			amount = amount.add(a.getPrize());
		}
		// 2º Get bookings prize
		Set<Booking> bookings = s.getBookings();
		for (Booking b : bookings) {
			amount = amount.add(b.getDiningHall().getPrice());
		}
		return amount;
	}