Can I have a documented "one way airline ticket" from USA to China for a tourist visa or roundtrip?

1. I will be applying for a tourist visa (6 months with multiple entries) for China in 2 weeks from the Consulate General of Peoples Republic of China. Do I need to have a "round trip airline ticket" from USA to China and back or can I have a "one-way" airline ticket to China!?
2. Also my USA passport is good until September 26, 2019 then I will apply for renewal Do I need a USA passport that has a longer duration than just 4 months? Thank You! Curt Williams , USA Citizen.