The answer is B, but I need to solution

3. William and Kate are planning on selling their family home which they own (valued at $500,000) and moving to a more expensive area where they will need to pay around $850,000 for their new residence. If they borrow the difference from their bank at 7.2% pa with a term of 25 years, how much (to the nearest $50) will their monthly repayments be? A. $3,550 B. $2,500 C. $3,000 D. $2,100