The exterior angles of triangle UVW are XX, ZY, and Z, and they are adjacent to _U, XV, and _W, respectively. If mW is 55°, and mY is 87°, what is mU?

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Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?

X+ 4y − z = −14 5x + 6y + 3z = 4 −2x + 7y + 2z = −17