[单选题]
A cart starts from rest and accelerat-u8;9 nrzc; a(gpfh8 fezb(wdv;dme 2e8 0gdb;cr8ykfpmj2 +ss at $4.0 \; m/s^2$ for 5.0 s, then maintain that velocity for 10 s, and then decelerates at the rate of $2.0 \; m/s^2$ for 4.0 s. What is the final speed of the car?
