If a silver alloy that costs $6.50 an ounce is going to be mixed with 30 ounces of a
silver alloy that costs $9 an ounce to
make a mixture that costs $8 an ounce,
how many ounces of the $6.50 an ounce
alloy must be used?

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)