Jody is trying to find out how much salt will dissolve in 200 ml of water. she adds salt to the beaker of water, but the salt seems to
just sit on the bottom of the beaker. what can jody do to the salt dissolve?

There are three things you can do to dissolve the salt in water:

1) Stir the solution - you increase the rate at which water molecules will come in contact with the salt crystals

2) Grind the salt - the surface area of the salt will increase thus the contact area between ionic lattice of the crystal that can interact with water, is bigger

3) Increase the temperature - this will increase even more the rate of the solvation by increasing the kinetic energy of the particles

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.