A rock is dropped from a cliff. Approximately how long does it take to fall 45m if the acceleration due to gravity is 9.8 m/sec2

Aracecar driver has to hold on tightly when going around a banked curve. approximately what is the centripetal force on a 2220.0 kg car going around a circle with a diameter of 190.0 meters at 25.0 m/s?

What does si stand for, when referring to a system of measurement

Can you match these to the correct definition