Implement the executeLoad$(),$ executeStore$(),$ executeJump$(),$ executeSub$()$ and executeAdd$()$ functions. Each of these has individual unit tests for them, so you should implement each one individually. All of these should be relatively simple $1$ or $2$ lines of code function if you reuse some of the previously implemented function. For example for the executeLoad$()$ function, you should simply be able to use peekAddress$()$ to get the value referenced by the irAddress member variable, then store this value into the accumulator.