Final answer:
The caller and callee use the $ra register to store the return address. The return address helps the callee know where to return control after completing its execution. The $ra register is used in function calls in programming.
Step-by-step explanation:
The caller and callee are terms commonly used in computer programming, specifically in regard to function calls. The $ra (return address) is a register that is used to store the address of the instruction following a function call.
When a function is called, the caller places the return address in the $ra register before jumping to the called function. The return address allows the callee to know where to return control once the called function finishes executing.
For example, let's say there is a main function that calls another function named foo. When main calls foo, the return address of the instruction following the function call in main is stored in $ra. Once foo finishes executing, it can use the value in $ra to return control back to the instruction following the function call in main.