$2.$ Show the register connections needed to implement the following data transfers:

P: R$2$R$1,$ R$1$ R$2$

$3.$ Are the operations in Problem #$2$ above microoperations? What does the comma denote in the above notation?

$4.$ Show how you can connect the output of two registers $($Ro and R$1)$ together to form a common data bus. Assume each register has $8$ bits. What size MUXes are needed? How many MUXes are needed?