HELP PLEASE! ONLY REAL ANSWERS. A researcher posts a newspaper advertisement offering $10 in exchange for participation in a short study. The researcher accepts the first 10 people who respond to the advertisement. Which of the following statements is true about the sample? It is not a valid sample because it is only a short study.
It is a valid sample because money is offered to participants.
It is a valid sample because the first 10 people were selected to participate.
It is not a valid sample because it is not a random sample of the population.

Which value is not a solution of 8x^3 – 1 = 0

The linear combination method is applied to a system of equations as shown. 4(.25x + .5y = 3.75) → x + 2y = 15 (4x – 8y = 12) → x – 2y = 3 2x = 18 what is the solution of the system of equations? (1,2) (3,9) (5,5) (9,3)

In new york city at the spring equinox there are 12 hours 8 minutes of daylight. the longest and shortest days of the year very by two hours and 53 minutes from the equinox in this year the equinox falls on march 21 in this task you use trigonometric function to model the hours of daylight hours on certain days of the year in new york city a.what is the independent and dependent variables? b.find the amplitude and the period of the function. c.create a trigonometric function that describes the hours of sunlight for each day of the year. d. graph the function you build in part c. e. use the function you build in part c to find out how many fewer daylight hours february 10 will have than march 21. you may look at the calendar.