What is 300+70+5/10+8/100 what decimal is it

How do you create a data set with 8 points in it that has a mean of approximately 10 and a standard deviation of approximately 1?

Which of the following represents the range of the graph of f(x) below

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)