Task: Question Generation
Input (English): Background Paragraph: About 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, in which water erodes the limestone over thousands to millions of years. Most cave systems are through limestone bedrock. 
Story: Bill is going on some trips this week. The first trip on Saturday is to Reginald's Peak. The next trip on Sunday is to Smuggler's Caves. He is very excited to see what both of the sites have to offer!.
Output (English): On which day will Bill have a better chance to see limestone formations?