4 A cereal manufacturer claims that \(25 \%\) of cereal packets contain a free gift. Lola suspects that the true proportion is less than \(25 \%\). In order to test the manufacturer's claim at the \(5 \%\) significance level, she checks a random sample of 20 packets.
- Find the critical region for the test.
- Hence find the probability of a Type I error.
Lola finds that 2 packets in her sample contain a free gift.
- State, with a reason, the conclusion she should draw.