Amelia's reliable fencing co. prices fences based on the amount of fencing installed plus a fixed amount of $200. the company charges $4 per foot of standard fencing. which of the following scenarios is correct?

it costs $1480 to enclose an 80′ by 80′ rectangular area.
it costs $2600 to enclose a 10′ by 60′ rectangular area.
it costs $1040 to enclose a 90′ by 40′ rectangular area.
it costs $560 to enclose a 50′ by 40′ rectangular area.

One of the inventors of integrated circuits observed that the number of transistors that fit on an integrated circuit will double every 24 months. what type of relationship most appropriately models this situation?

Satchi found a used bookstore that sells pre-owned dvds and cds. dvds cost $9 each, and cds cost $7 each. satchi can spend no more than $45.

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 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)