i dont think the medicare answer is correct and the last part

Calculate the following amounts for a participating provider who bills Medicare Submitted charge $75 Medicare physician fee schedule $60 Coinsurance amount $12 Medicare payment (80%) 48 Medicare write-off 15 Calculate the following amounts for a nonPAR who bills Medicare Submitted charge $650 NonPAR Medicare physician fee schedule allowed amount $450 Limiting charge (115% of MPFS allowed amount) 491 Medicare payment (80% of the MPFS allowed amount) 342 Beneficiary is billed 20% plus the balance of the limiting charge $157.50 Medicare write (NOT to be paid by Medicare or beneficiary) 158 3. Calculate the non-par limiting charge for a MPFS allowed charge of $75 4. Calculate the non-par allowed charge for a MPFS amount of $75