Assume that the classes listed in the Java Quick Reference have been imported where approp

Assume that the classes listed in the Java Quick Reference have been imported where appropriate. $-$ Unless othervise noted in the question, assume that parameters in method calls are not null and that methods are called only when their preconditions are satisfied.

This question involves the AppointmentBook class, which provides methods for students to schedule appointments with their teacher. Appointments can be scheduled during one The AppointmentBook class contains two helper methods, isMinuteFree and reserveBlock. You will write two additional methods of the AppointmentBook class. public class AppointmentBook

public class AppointmentBook

$**$ Returns true if minute in period is available for an appointment and returns $*$ false otherwise $*$ Preconditions: $1$ c period $8$;$0$ minute $=59$

$/***$ Marks the block of minutes that starts at startMinute in period and $*$ is duration minutes long as reserved for an appointment

is duration minutes long as reserved for an appointment $*$ Preconditions: $1$ period $8$;$0<mi\; id="EditorElement\_2112242"></mi>$ startMinute $59$; $*1<mi\; id="EditorElement\_2112190"></mi>$ duration $60$

$*/$ private void reserveBlock$($int period, int startMinute, int duration$)$ implementation not shown

$/***$ Searches for the first block of duration free minutes during period, as described in $*$ part $($a$).$ Returns the first minute in the block if such a block is found or returns $-1$ if no $*$ such block is found.

such block is found. $*.$ Preconditions: $1$ period $8$;$1$ duration $60*/$

$*\frac{*}{?}$ public int findFreeBlock$($int period, int duration$)$ to be implemented in part $($a$)$

$/***$ Searches periods from startPeriod to endPeriod, inclusive, for a block $*$ of duration free minutes, as described in part $($b$).$ If such a block is found, $*$ calls reserveBlock to reserve the block of minutes and returns true; otherwise

returns false. Preconditions: $1$ startPeriod $$ endPeriod $<mi\; id="EditorElement\_2111296"></mi><mn\; id="EditorElement\_2111298">8</mn>$;$1<mi\; id="EditorElement\_2111306"></mi>$ duration $<mi\; id="EditorElement\_2111269"></mi><mn\; id="EditorElement\_2111271">6</mn><mn\; id="EditorElement\_2111272">0</mn>$

$\}/$ There may be instance variables, constructors, and methods that are not shown.

Consider the following list of unavailable and available minutes in period $2$

The method call findFreeBlock $(2,15)$ would return $30$ to indicate that a $15-$minute block starting with minute $30$ is available. No steps should be taken as a result of the call to findF reeBlock to mark those $15$ minutes as unavalable

The method call findFreeBlock $(2,20)$ would return $-1$ since no $20-$minute

$/***$ Searches for the first block of duration free minutes during period, as described in $*$ such block is found.

blic int findFreeblock $($int perion $8$;$1$ duration $60$

B