Please show detailed help with steps on how to solve, and why answer is what it is :

For years, MedMax believed that a 10% markup covered its selling and adminstrative expenses and provided a reasonable profit. However, in the face of declining profits Med Max decided to implement an activity based costing system to help its understanding of customer profitability. The company broke its selling and adminstrative expenses into five activities as shown below :

Activity Cost Pool : Customer Deliveries Activity Measure : Number of Deliveries Total Cost : 332,000 Total Activity : 4,000 deliveries

Activity Cost Pool : Manual Order Processing Activity Measure : # Manual Orders Total Cost : $300,000 Total Activity : 6,000 orders

Activity Cost Pool : Electronic Order Processing Activity Measure : # Electronic Orders Total Cost : 312,000 Total Activity : 12,000 orders

Activity Cost Pool : Line Item Picking Activity Measure : # Line Items Total Cost : 1,100,000 Total Activity : 440,000 line items

Total Selling and Admin Expenses : $2,644,000

Med Max gathered the data below for two of the many hospitals that it serves --- City General and County General (each hospital purchased medical supplies that had cost Med Max $42,000 to buy from its manufacturers) :

Activity Measure :

Number of Deliveries : City General : 35 County General : 15

Number of Manual Orders : City General : 0 County General : 25

Number of Electronic Orders : City General : 15 County General : 0

Number of Line Items : City General : 160 County General : 200

Question : The customer margin for City and County General hospitals are : (listed in order of City and County) :

A) 3,800 and 3,700

B) 4,200 and 2,950

C) 3,810 and 4,200

D) 505 and 1,205

E) None

Solution manual shows D) but I don't get how or why