A security alarm requires a four-digit code. The code can use the digits 0–9 and the digits cannot be repeated. Which expression can be used to determine the probability of the alarm code beginning with a number greater than 7? A. (2 P 1) (9 P 3) /10 P 4 B. (2 C 1) (9 C 3)/10 C 4 C. (10 P 1) (9 P 3)/10 P 4 D.(10 C 1) (9 C 3)/10 C 4

What are the soultion(s) to the quadratic equation 40- x^2=0

Combine the information in the problem and the chart using the average balance method to solve the problem.

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)