Which values of x and y would make the following expression represent a real number? (4 + 5i)(x + yi) x = 4, y = 5 x = –4, y = 0 x = 4, y = –5 x = 0, y = 5

Consider that lines b and c are parallel. what is the value of x? what is the measure of the smaller angle?

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables