Answer :
The answer is $3150,9. It's because biweekly is 2 weeks and one month is generally 4 weeks, so we just double the number and we'll get the monthly average. Easy as it is :)
a moth has four weeks so the average monthly income is:
1,575.45$ *2= 3150.9$ aproximative 3151$ per month
1,575.45$ *2= 3150.9$ aproximative 3151$ per month