Which of the following equations demonstrate that the set of polynomials is not closed under the certain operations? O A. Subtraction: 3*+ **)-(-224 + 2) = 544 O B. Multiplication: (-5%+3)(-5) = 22 - 10/2 +28% -15 O C. Division: (1-5%+3) -(%-2) = %-3+ % - 2 D. Addition: (x2 + x) + (x + 1) = x2 + 2x+1 SUBMIT

Atest of sobriety involves measuring the subject's motor skills. a sample of 31 randomly selected sober subjects take the test and produce a mean score of 64.4 with a standard deviation of 2. a claim is made that the true mean score for all sober subjects is equal to 65. for each part below, enter only a numeric value in the answer box. for example, do not type "z =" or "t =" before your answers. round each of your answers to 3 places after the decimal point. (a) calculate the value of the test statistic used in this test. test statistic's value = (b) use your calculator to find the p-value of this test. p-value = (c) use your calculator to find the critical value(s) used to test this claim at the 0.2 significance level. if there are two critical values, then list them both with a comma between them. critical value(s) =