Abdullah is a quality control expert at a factory that paints car parts. He knows that 20 % 20% of parts have an error in their painting. He recommended a change in the painting process, and he wanted to see if this error rate had changed. He took a random sample of 400 parts painted in a month and found that 60 had an error. He wants to test H 0 : p = 0.2 H 0 :p=0.2H, start subscript, 0, end subscript, colon, p, equals, 0, point, 2 versus H a : p ≠ 0.2 H a :p  =0.2H, start subscript, start text, a, end text, end subscript, colon, p, does not equal, 0, point, 2, where p is the proportion of all parts with the error in their painting that month. Assuming that the conditions for inference Abdullah is a quality control expert at a factory that paints car parts. He knows that 20 % 20% of parts have an error in their painting. He recommended a change in the painting process, and he wanted to see if this error rate had changed. He took a random sample of 400 parts painted in a month and found that 60 had an error. He wants to test H 0 : p = 0.2 versus p, is the proportion of all parts with the error in their painting that month. Assuming that the conditions for inference have been met, calculate the test statistic for Abdullah's significance test. have been met, calculate the test statistic for Abdullah's significance test. z=