In the united states woman earn cents for each dollar that a man earns. Can this be explained? What are the reasons?

In retail sales, women earn 70 cents to the dollar while a man with the same title will earn nearly $40,000 more a year african-american women make 64 cents and Latina-americans make 56 cents for every dollar earned by a caucasian-american man. The only explanation i can give is that even though we are all born and created equally we are not treated equally, and there is extremes on every side and we should all just try to live life and let others believe what they wanna believe and try to live peacefully regardless of race religion color creed or sexual orientation. Just be the best you believe you can be and prove them wrong so they see that there can be peace.