An observer has determined that the time headways between successive vehicles, on a section of highway, are exponentially distributed and that 65% of the headways between vehicles are 9 seconds or greater. if the observer decides to count traffic in 30-second time intervals, estimate the probability of the observer counting exactly four vehicles in an interval. (in decimal, round to the 4th decimal place)

Ms. sutton recorded the word counts and scores of the top ten essays in a timed writing contest. the table shows her data. how does the word count of an essay relate to its score in the contest? word count tends to decrease as the score decreases. word count tends to increase as the score decreases. word count tends to remain constant as the score decreases. word count has no apparent relationship to the score of the essay.

Graph the equation. select integers for x

An initial investment of $100 is now valued at $150. the annual interest rate is 5%, compounded continuously. the equation 100e0.05t = 150 represents the situation, where t is the number of years the money has been invested. about how long has the money been invested? use your calculator and round to the nearest whole number. years