Clicking the Causes Uses button in the Equation Panel for a variable is an easy way to see both the variables that are included in the calculation of that variable
and other variables that use it's value for their calculations.
The button is above the equation box for stocks, flows and converters and looks like a two sided arrow. Clicking on the arrow gives you two choices, Causes and Uses.
If you click on Causes for a flow, for example, the list of the other variables used to calculate (or cause) the flow value will show. If you click on Uses,
a list of the other variables that use the flow to calculate their values appears.