The Bookmark is an online bookseller. When books are purchased, the shipping fees are added to the price. The table shows how shipping fees are calculated
Purchase Total
Less than $20
$20-$34.99
$35-$49.99
Greater than $50
Shipping Fees
3% of total
4% of total
6% of total
8% of total
Sonja bought 3 books priced at $11.35, $9.50, and $14.70.
Part A . Determine the shipping fees for Sonjas order . Round the answer to the nearest hundredth if necessary. $
Part B. What is sonjas total cost including shipping .$

Jeffery conducted a survey in his school and found that 30 of the 50 eighth grade students' favorite subject is mathematics. based on the results, jeffery concluded that out of the 200 students in his school, 120 students' favorite subject is mathematics. select the statement that is true about jeffery's conclusion. a. jeffery's conclusion is not valid because the sample was biased since only 200 students were surveyed. b. jeffery's conclusion is valid because the sample was random since all of the students were eighth grade students. c. jeffery's conclusion is valid because the sample was random. d. jeffery's conclusion is not valid because the sample was biased since all of the students were eighth grade students.

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