Cuanto mide la apotema de un octagono regular si cada lado mide 3.5 y su area es de 60.24

Plz me plz i will give a brain just plz

Mr. and mrs. wallace have decided to buy a car for $21,600. they finance $15,000 of it with a 5-year auto loan at 2.9% arp. what will be their monthly payment be? a. $268.20 b. $268.86 c. $269.54 d. $387.16 (monthly car loan payment per $1,000 borrowed) i need !

Ineed someone to me answer my question i have to have this done and knocked out