You have a choice between a​ 30-year fixed rate loan at ​% and an adjustable rate mortgage​ (ARM) with a first year rate of ​%. Neglecting compounding and changes in​ principal, estimate your monthly savings with the ARM during the first year on a ​$ loan. Suppose that the ARM rate rises to ​% at the start of the third year. Approximately how much extra will you then be paying over what you would have paid if you had taken the fixed rate​ loan?