Consider an order handling process with different causes of errors and the corresponding frequencies as in the table below.

Cause of errors	Frequency of resulting errors
Browser error	24
Order number out of sequence	21
Products shipped, but credit card not billed	9
Order entry mistake	32
Products shipped to billing address, not shipping address	36
Wrong model shipped	42

(a)[1] Sort the frequencies from the highest to the lowest values. (b)[1] Calculate percentages and cumulative percentages (e.g. 23.4%). Show your work. (c)[1] Manually draw a Pareto diagram of the percentages, which includes a percentage ogive.

(d)[1] Use Excel to draw a Pareto diagram of the percentages with a percentage ogive. (e)[1] What cause(s) of errors should the company focus on? (Your opinion & short elaboration)