Valeria is playing with her accordion. The length of the accordion A(t)A(t)A, left parenthesis, t, right parenthesis (in \text{cm}cmstart text, c, m, end text) after she starts playing as a function of time ttt (in seconds) can be modeled by a sinusoidal expression of the form a\cdot\cos(b\cdot t)+da⋅cos(b⋅t)+da, dot, cosine, left parenthesis, b, dot, t, right parenthesis, plus, d. At t=0t=0t, equals, 0, when she starts playing, the accordion is 15\text{ cm}15 cm15, start text, space, c, m, end text long, which is the shortest it gets. 1.51.51, point, 5 seconds later the accordion is at its average length of 21\text{ cm}21 cm21, start text, space, c, m, end text. Find A(t)A(t)A, left parenthesis, t, right parenthesis. \textit{t}tstart text, t, end text should be in radians.

Afriend of mine is giving a dinner party. his current wine supply includes 10 bottles of zinfandel, 8 of merlot, and 11 of cabernet (he only drinks red wine), all from different wineries. (a) if he wants to serve 3 bottles of zinfandel and serving order is important, how many ways are there to do this? ways (b) if 6 bottles of wine are to be randomly selected from the 29 for serving, how many ways are there to do this? ways (c) if 6 bottles are randomly selected, how many ways are there to obtain two bottles of each variety? ways (d) if 6 bottles are randomly selected, what is the probability that this results in two bottles of each variety being chosen? (round your answer to three decimal places.) (e) if 6 bottles are randomly selected, what is the probability that all of them are the same variety? (round your answer to three decimal places.)