Agroup of 19 students want to see the show at the planetarium. $11 for each student who is a member of the planetarium's frequent visitor program and $13 for each student who is not a member. the total cost of the students' tickets is $209. let x represent the number of students in the frequent visitor program. write an expression in the group who are not members.

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)