Is -0.89 a strong negative correlation?

Find all the angles that satisfy the equation cos(θ)=32

The weekly amount spent by a company for travel has an approximately normal distribution with mean = $550 and standard deviation = $40. a) what is the probability that the actual weekly expense will exceed $570 for more than 20 weeks during the next year? (note: one year = 52 weeks) b) what is the probability that actual weekly expenses exceed $580 for 10 or more, but 16 or fewer weeks during the next year?

Find the x-intercepts for the parabola defined by this equation: y=-3x^2-6x+9