How many six-letter "words" (sequences of letters with repetition) are there in which the first and last letter are vowels? in which vowels appear only (if at all) as the first and last letter? comment on these possible answers to the second part: (a) 52214, (b) 52264, (c) 212264, and (d) 266 − 212264

6.(q^9)^2 a. 2q^18 b. q^18 c. q^81 d. q^11 7.(6q^6)^-4 a. 6q^1296 b. 1296q^2 c. 1/1296q^24 d. 6q^-24 8. what is the value of 12x^-3 y^-1 for x = -1 and y = 5? a. -12/5 b.-10 c.-0 d.5/12 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

Through non-collinear points there is exactly one plane.

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.