Question

explain how the length of the plateaus on a heating curve for water could be changed (2 ways)

Answer 1

A larger amount of water will lengthen the plateau. A smaller amount of water will shorten the length of the plateau.

Answer 2

Right changing the mass so that's one way but i need another :<

Answer 3

I thought I answered thee question. The length can be shortened (1 change) or lengthened (2nd change) by chaning the mass of the water. So now you want a ANOTHER WAY to make it longer or shorter. What about changing the rate of heating. Slower heating takes longer to complete the phase change from ice to liquid or from liquid to steam.
1. Change the mass of the water.
2. Change the rate of heating/cooling.