PLEASE HELP WITH THE FOLLOWING 3 QUESTIONS (Show steps thank you:)). 1. when you are 20 years old, you watch Superman (age 40.0) leave Earth on an important mission. He is capable of flying at 2.70 x 10^8 m/s. He finally arrives back at Earth when you are 62.0 years old. How old is Superman?

2. Rick is filming a movie in space and he is travelling so fast that he appears to you on earth to have 9.00 times his normal mass. How fast is he travelling?

3. A human's average life span is 80.0 years. How long in earth years would the average human live if they were travelling around the universe at 0.856c?