There are 10 balls of three kinds in the bag, marked with numbers 2, 3, and 5 respectively, and 10 balls are drawn out of them. If the sum of the numbers on these 10 balls is 33, how many balls marked with the number 2 can be drawn at most? ball.
袋子里有三种球各10个，分别标有数字2，3，5，从中摸出10个球、若这10球上的数字之和是33，那么最多摸出了多少个标有数字2的球．
<result>5</result>