Do i need to find each squares thing or just 4•2•9

Alaptop computer is purchased for $1350 . after each year, the resale value decreases by 30% . what will the resale value be after 5 years?

9. (y^-5)^10y^10 a. y^-60 b. y^60 c. y^-150 d. y^150 find the simplified form of each expression. 10. (4/7^5)^2 a.8/14^10 b.16/49^25 c.16/49y^10 d.8/14y^25 11. determine if the number 3.43 times 10^-6 is written in scientific notation. if not, explain. a. yes; the number is written scientific notation. b. no; the first factor is not a number between 1 and 10. c. no; it is not written as a number times a power of 10

If n stands for number sold and c stands for cost per item, in which column would you use the formula: ? a. column d c. column f b. column e d. column g