11. Find the product: (50z + 20)(10z + 4) ( 1 ) 12. Find the product: (88a + 80)(8a + 8) ( 1 ) 13. Find the product: (40y + zy)(4y + zy) ( 1 )

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)

I’m not good at math can i have ? ?

Study results indicate that the mean length of time people spend on a bus in a city is between 21.2 min and 24.5 min what is the study margin of the error?