Consider two computer systems A and B. For A, a branch is implemented by two instructions:

Sub $3, $1, $2 #$3=$1-$2

Branch $3, 300 #take the branch if $3=0

For B, the compare is included in the branch instruction as in the MIPS architecture

Beq, $1, $2, 300

All other instructions of the two machines are the same and on both machines, the instructions take the same number of cycles. The instruction frequency of machine A is shown in the following table. Since in a single instruction, machine B has to test the condition as well as handle the branch, the cycle time of machine B is 25% longer than A.

Instrunction type	%	Clock cycle count
ALU ops	47	1
Loads	21	2
Stores	12	2
Branchs	20	2

1. What is CPI of A? CPI of B? 2. Execution time of A? Execution time of B? 3. Which one if faster? By how much?