Can you please help me I will give out the brain thing and extra points please help me. Danielle is ordering costumes for her dance recital. The company Danielle is ordering from charges $19 per costume and a shipping fee of $9.

Based on this information, which function can be used to represent the relationship between the total cost, k, and the number of costumes Danielle orders, u?

k=19u−9

k = 9u + 19

k = 19u + 9

k=9u−19

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)