sale revenue to be recognized in 31 dec 2019

and maintanence revenue to be regognized in 31 dec 2019

answer with clear steps

On Jan the 1st 2019, ABC Company signed a contract with XYZ company to supply them with 1000 computers for $500,000. The contract includes maintenance for the computers for 2 years. ABC considered these unrelated performance obligations, fair value for the computers was $400 each. sales revenues to be recognized on 31st Dec 2019 is