Meaning of level of significance and its relation to p-value

A sample of \(100\) batteries is taken from a population with mean lifetime \(12\) hours and the following are obtained:

\(\sum x = 1180\) and \(\sum x^{2} = 15536\)

A statistical test is carried out at \(10\%\) level of significance and it is found that the population mean lifetime is not \(12\) hours.

1. State what you understand by the expression at \(10\%\) significance level in the context of the question.
2. Find the range of level of significance at which the test will indicate that the population mean lifetime is not \(12\) hours.