Three work study analyst are reading an employee work study analyst one rates the employee at performance rating factor equal to one in an observed time of $2\mathrm{.}8$ minutes per unit work study analyst two rates the employee at PRF equal to $1\mathrm{.}1$ and an OT of $3\mathrm{.}1$ minutes per unit work study analyst three rates employee PRF equal to $0\mathrm{.}8$ in an OT of $3\mathrm{.}0$ minutes per minute for unit what should standard time be assuming an allowance factor of $20\%$