for propertional controller the controled variable is a process temperature with a range of $50-130$c and a setpoint of $73\mathrm{.}5$c under nominal conditions,the setpoint is maintained with an output of $50\%.$ find the propertional offset resulting from theload change that requires a $55\%$ output in the propertional gain is a$.0\mathrm{.}1$ b$.0\mathrm{.}7$ c$.2\mathrm{.}0$ d$.5\mathrm{.}0$