Plz help it's due at midnight

Ais useful when you need a simple machine to you separate two things. a. lever b. screw c. pulley d. wedge

Acaterpillar tries to climb straight up a wall a meter high, but for every 2 cm up it climbs, it slides down 1 cm. eventually, it reaches the top. when it reaches the top, it does not pull itself over so it will slide down 1 cm. what is the total displacement traveled?

How many atoms of nitrogen are in the chemical formula ni(w on