Please explain,; Looking for the alpha value???

Consider the following exponential averaging formula used to predict the length of the CPU burst time for the next process under the SJF scheduling policy. Given below is an equation expressed in terms of ?, Tcurrent, and ?o. Use the equation to find the optimal value of ? for each of the given pairs of values under (i) and (ii). And then, find the two values of ?next using these two values of ?. Which ?next is preferred assuming that the next processs behavior is close to the current ones behavior? [Show each step of your calculations only in the spaces provided. ?next = ? . Tcurrent + (1 ?) 2 . ?o

where ?next is the predicted next processs burst time,

Tcurrent is the current processs burst time

?o is the average burst time of all the past processes, and 0 ? ? ? 1 i) Tcurrent = 20msec and ?o = 100 milliseconds ii) Tcurrent = 60msec and ?o = 75 milliseconds