An ice cream truck travels down a street at 5.00 m/s and plays a frequency of 420 Hz. A boy runs after the truck (in the same direction). The boy hears a note of frequency of 427 Hz.a) Is the boy catching up to the truck, or falling behind?
b) At what speed is the boy running?
c) When the boy is 18.0 m from the truck, the sound has a sound level of 68.0 dB. What is the power of the speaker on the truck?
One card is selected at random from a deck of cards. Determine the probability that the card selected is a card greater than
and less than
A medical research team conducted a double-blind study to test the effect of a new arthritis medication. At the end of the study, the researchers found that of the 250 subjects who took the medication, 133 reported significant pain relief from arthritis pain. Of the 251 subjects who took the placebo, 105 reported significant pain releif from arthritis pain. At the 1% significance level, can you conclude that the pain relief from the arthritis pain is greater for those who took the medication than for those who took the placebo?State the hypothesis, check the conditions, find the test statistic, and the p-value. State your conclusion in context.
In a survey of 1825 randomly-selected adult Australian internet users, 1523 said that they obtain health information on the internet.
(a) Use these data to evaluate the evidence that at least four-fifths of adult Australian internet users get health information from the internet. Assume α = 1%, use a P-value approach, and include all relevant steps of a formal hypothesis test. 
(b) Can the conclusion from part (a) be generalised to the Australian adult population? Explain why or why not.
What is the probability of randomly selecting a two from a standard 52 card deck
If there is a relationship between drug use and violence, then an individual should engage in more violent incidents after they have begun using drugs as compared to before they began using drugs. You ask a sample of 4 women to report the number of violent incidents they have been involved in during the month before they began using drugs. You then ask these same 4 women to report the number of violent incidents they were involved in since during the month after they began using drugs. These results are reported below.Woman Before Drug Use After Drug UseJane 1 3Betty 1 3Wilma 2 1Ginger 1 4Test the null hypothesis that the number of violent incidents before and after the initiation of drug use is the same against the alternate hypothesis that the number of violent incidents increased after the initiation of drug use. Use alpha = .01. Be sure to show all steps of your hypothesis test.(To receive full credit you should show your work by uploading a photo of your scratch paper along with your submitted answer.)
A travel weekly international air association asked travelers about the purpose for their recent business trip. 19% responded that it was for an internal company visit. Suppose 950 business travelers are randomly selected. What is the probability that between 18-20% of the business travelers say that the reason for their most recent business trip was an internal company visit?
Maria invests a total of $16,000 in two accounts. The first account earned a rate of return of 5% (after a year). However, the second account suffered a 4% loss in the same time period. At the end of one year, the total amount of money gained was $-460.00. How much was invested into each account?