A program is outputting a series of blocks by repeatedly issuing an I$/$O instruction.

Executing the I$/$O instruction takes $1$ unit of CPU time. All other instructions take $0$ units of time.

The device starts at the end of the I$/$O instruction and remains busy for $6$ time units.

When polling is used, the CPU polls the device every $5$ time units.

A poll takes $1$ unit of CPU time.

When interrupts are used, the interrupt handler takes $3$ time units to process the interrupt.

$($a$)$ Draw a timing diagram showing when the CPU and the device are busy during the first $24$ time units

with polling

with interrupts