② When throwing two coins, the probability of "both heads up" and "both tails up" are 14 respectively, and the probability of "just one coin heads up" is 12, so ② is incorrect;
(3) The lottery is sequential, and the lottery order has no effect on the winning rate, so (3) is correct;
④ Because the basic events are infinite and the possibility that a point falls on any point in a circle is equal, the mathematical model of random test is geometric probability, so ④ is correct.
So the answer is: ③ ④.