A service process has three stages. The error percentages are: $6\%$ at stage one, $8\%$ at stage two, and $7\%$ at stage three. The connection logic of the three stages is that a good overall outcome happens when at least two stages individually have good outcomes. $($a$)$ Draw the event tree for this situation with all necessary details. $($b$)$ Find the probabilities of defective and good overall outcomes $(5$ decimals$).($c$)$ Calculate and interpret the EPMO of this process $(2$ decimals$).($d$)$ Calculate the sigma level of the process $(2$ decimals$)$ and state it$.$ Sketch the sigma level. Hint: The following table provides help in your sigma level calculation. $0\mathrm{.}99304,0\mathrm{.}98607,0\mathrm{.}97911,0\mathrm{.}97214,0\mathrm{.}96518$ NORM S INV$($av$)2\mathrm{.}46,2\mathrm{.}20,2\mathrm{.}04,1\mathrm{.}91,1\mathrm{.}81$