[单选题]
A cart starts from re z69y no1ixivp oc//8ystaxr63hog-8 z: i yn7dk and accelerates 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?
