Phase change is the change in state. i.e. water to steam or ice to water
The greatest threats to coral reefs is the rising temperature of the oceans as a result of climate change and the acidification of the oceans due to increased levels of carbon dioxide in the atmosphere which dissolves in the ocean and forms carbonic acid.Aug 3, 2015
The variables are defined as the factors in an experiment, which are liable to change. The variable can be dependent or independent. The Independent variable is a variable, which is unaffected by the changes in the other variables.
In this case, the brand of the food Shara feeds to the rats is independent factor, but it is changes in the system, so, it is an independent variable.
The effect on the weight of the rat is dependent on the brand of food they are consuming. So, the weight of rats is dependent variable.