Problem $5.$ The monthly demand for product K has been as follows in the last six months:

January $500$

February $450$

March $550$

April $500$

May $600$

June $550$

a$.$ Make a forecast for July, using exponential smoothing with $\backslash$alpha $=0\mathrm{.}3,$ if the forecast for

January was $550.$

b$.$ Calculate MAD, RSFE $($running sum of forecast errors$),$ and tracking signal for forecasts

from February through June.