What's the definition of wavelength?

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

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?

It is really hard for me right know