$3.(20)$ Assume that memory contains three holes of $10$ MB each. A sequence of $14$ requests for $1$ MB each is to be processed. For each of the memory allocation methods listed below, determine the sizes of each of the remaining holes after all $14$ requests have been satisfied $($assume that the direction of searching the holes is from top to bottom or left to right$)$:

a$.$ first fit

b$.$ best fit

c$.$ worst fit

$4.(10)$ Consider the working set model with $\backslash (\backslash$Delta$=3\backslash ).$ Given the following reference string of a process p :

$\backslash [$

y x x x x x x y y u x x x y z y z w w z x x w w

$\backslash ]$

a$.$ What is the largest working set process $\backslash ($ p $\backslash )$ will ever have?

b$.$ What is the smallest working set process $\backslash ($ p $\backslash )$ will ever have $($not counting the first $\backslash (\backslash$Delta $\backslash )$ references$)?$