Petra is making necklaces to sell at a craft fair. The hardware for each necklace costs $3.75, and each bead costs $0.50. The number of beads Petra needs depends on the design she chooses. Which expression gives the total cost to make 30 necklaces with b b beads?

What is the ratio if counted 14 robins out of 150

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)

How can constraints be used to model a real-world situation?