On the first day of a conference, 10 rows of 6 chairs are set out in a meeting room. the second day, in the same room, 3x more rows with 5x more chairs are set out. which of the following equations could be used to determine the number of chairs set out in the meeting room on the second day? a. y = (15x^2 + 60) chairs b. y = (15x^2) chairs c. y = (15x^2 + 16) chairs d. y = (15x^2 +68x +60) chairs

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)