No. Rejecting the Null Hypothesis means that there is a high degree of probability that it is not correct. This degree of probability is the critical level that you choose for the test statistic. However, there is still a small probability that the null hypothesis was correct.
No, you are never certain.
int, float: 0 pointer: NULL
That is the correct spelling of the word "declaration" (a statement).
No, that is not the correct definition.
Yes it can as long as the context is correct
A Type I error is committed whenever a true null hypothesis is rejected. A Type II error is committed whenever a false null hypothesis is accepted. The best way to explain this is by an example. Suppose a company develops a new drug. The FDA has to decide whether or not the new drug is safe. The null hypothesis here is that the new drug is not safe. A Type I error is committed when a true null hypothesis is rejected, e.g. the FDA concludes that the new drug is safe when it is not. A Type II error occurs whenever a false null hypothesis is accepted, e.g. the drug is declared unsafe, when in fact it is safe. Hope this helps.
It's the Declaration of Independence. The thirteen colonies declared their independence from Great Britain.
CHANNEL : a waterway, conduit, or assigned frequency, pronounced "CHAH-null".
You may want to prove that a given statistic of a population has a given value. This is the null hypothesis. For this you take a sample from the population and measure the statistic of the sample. If the result has a small probability of being (say p = .025) if the null hypothesis is correct, then the null hypothesis is rejected (for p = .025) in favor of an alternative hypothesis. This can be simply that the null hypothesis is incorrect.
That is the correct spelling of "certification" (official confirmation or declaration).
No. The null hypothesis is not considered correct. It is an assumption, and hypothesis testing is a consistent meand of determining whether the data is sufficiently strong to say that it may be untrue. The data either supports the alternative hypothesis or it fails to reject it. See examples in links. Also note this quote from Wikipedia: "Statistical hypothesis testing is used to make a decision about whether the data contradicts the null hypothesis: this is called significance testing. A null hypothesis is never proven by such methods, as the absence of evidence against the null hypothesis does not establish it."