How to Use 了 le and 过 guo

Which of the following mean that the action of eating has occurred? 1a)Wǒ chīle.我吃了。我吃了 1b)Wǒ chīguo.我吃过。我吃过 1c)Wǒ chīguo le.我吃过了。我吃过了 All of them! Both 了 and 过 give the impression that something has occurred. How do you use...