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Determine the mean and variance of the random variable with the following probability mass function. f(x)=( 729divided by 91) (1 divided by 9) superscript x baseline comma x equals 1,2,3 round your answers to three decimal places (e.g. 98.765).

Afamily has five members. a mom, a dad, two sisters, & a brother. the family lines up single file. what is the probabillity that the mom is at the front of the line

Joline is solving the equation 0=x^2-5x-4 using the quadratic formula which value is the negative real number solution to her quadratic equation round to the nearest tenth if necessary