Which one of the 4 is the answer

4+6x-3x^3 in standard form with explanations because i don’t understand

Bradley hikes 12 miles in 3 hours. in relation to bradley’s hike, which statement describes the expression

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 !