The statistical process: hours of sleep a sleep researcher poses the question do children teenagers or adults get the most sleep she randomly selects groups of children teenagers and adults and ask them the average number of hours of sleep they get per night she records their responses in crates data displays for each group

step-by-step explanation: a reaction is first order. if the initial reactant concentration is 0.0200 m, and 25.0 days later the concentration is 6.25 x 10-4 m, then its half-life is:

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.