The drug penicillin was discovered by observation of mold growing on biology lab dishes. suppose a mold begins growing on a lab dish. when first observed, the mold covers 7 cm^2 of the dish surface, but it appears to double every day.
f. i. if the area of a mold patch is first measured to be 5 cm^2 and the area doubles each day, how long will it take that mold sample to grow to an are of 40 cm^2
f. ii. for how many days will the mold patch part i have an area less than 330 cm ^2

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)

If you apply the changes below to the linear parent function f(x)=x what is the equation of the new function vertically stretched by a factor of 3 flip over the x axis

3.4a=57.8 what is the the value of a