Jen earned x dollars on saturday and y dollars on sunday. she plans to save 25% of the money she earned over the weekend and spend the rest. write an expression for the amount of money jen saves. a. 0.25x+y b. 25(x+y) c. x+y d. 0.25(x+y)

Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Marla bought a book for $12.95, a binder for $3.49, and a backpack for $44.99. the sales tax rate is 6%. find the amount of tax and the total she paid for these items