solve的名词形式是什么?

　　It was only a partial solution to the problem.

　　那只是部分地解决了这个问题。

　　There's no obvious solution to the problem.

　　这个问题尚无公认的解决办法。

　　I managed to find a solution to the problem.

　　我设法找出了解决问题的办法。