a)
Parameter we are testing is population mean .
H0: = 14
Ha: < 14
b)
Test statistics
z = - / ( / sqrt(n) )
= 13.82 - 14 / (1.6 / sqrt(60) )
= -0.87
c)
Critical value-
At 0.01 level, critical value = -2.326
Since test statistics > -2.326, we do not have sufficient evidence to reject null hypothesis.
We conclude at 0.01 level that we fail to support the claim.
Question 6) Need more proteinll The manufacturer of a crao hage oy and ari stest tet...
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