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The mean of a set of data is -3.82 and its standard deviation is 2.31. find the z score for a value of 3.99.

True or false look at the picture pls : /

Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?