Which of the following statements are true? If false, explain briefly.
a) It is better to use an alpha level of 0.05 than an alpha level of 0.01.
b) If we use an alpha level of 0.01, then a P-value of 0.001 is statistically significant.
c) If we use an alpha level of 0.01, then we reject the null hypothesis if the P-value is 0.001.
d) If the P-value is 0.01, we reject the null hypothesis for any alpha level greater than 0.01.