If 'a' and 'b' stand for true sentences and 'c' and 'd' stand for false sentences, what is the truth-value of each of the sentences represented below? (circle t' or 'f.) t f 1 c b t f 2. a c b. a t f 3. t f 4. b. c t f 5. c (b a) 6 (c b)a t f t f 7 (a. b).c 8 t f (c a) t 9. (c b) f 10 b.(c a) t f t f 11 (b a).d t f 12. c(a-d) 13. (bd) t f 14 t f (c.(b d)) 15. (bc) t f

Jessa bought a yoyo from a company that claims that, with each retraction, the string rolls up by 60% of the original length. she sets up a tape measure and throws the yoyo 3 times. her data are charted below. throw length of string (feet) 1 3 2 1.8 3 1.08 jessa wants to find the sum of the length of string after 10 throws. what is the sum of the lengths, rounded to the nearest hundredth?