Here is a quick and easy way to solve this complicatedly worded problem.

Lets assume N= 100. Now Selling price is marked by 40%, so SP(Selling Price) is equal to 140, and the total profit is equal to 40. Now Shipping costs are 10% of the total Selling Price, so Shipping Costs are equal to 14. So Total Profit realized by the retailer is 40-14= 26.

Now what happens next? Shipping Cost increases to 12%, a total increase of 2%, so new shipping cost becomes 16.8. New Net profit realized is equal to 23.2.

So Total Percentage decrease in Net Profits is equal to \(2.8/26 * 100\) = approx. 10.7...

So answer is E

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we shall fight on the beaches,

we shall fight on the landing grounds,

we shall fight in the fields and in the streets,

we shall fight in the hills;

we shall never surrender!