Finance... guys please help me out for this with calculation, thanks!!!

Elysian Fields, Inc., uses a maximum payback period of 6 years and currently must choose between two mutually exclusive projects. Project Hydrogen requires an ini- tial outlay of $25,000; project Helium requires an initial outlay of $35,000. Using the expected cash inflows given for each project in the following table, calculate each project's payback period. Which project meets Elysian's standards? E10-1 Expected cash inflows Year- .,.. Hydrogen Helium $6,000 6,000 $7,000 2 7,000s 8,000 8,000 5,000 . 3,500 . ..: 5,000 4,000 4 4,000, . 2,000