purpose that piperidine acts as the base and helps form the enolate ion intermediate? Can you explain why it would not work as efficiently without it?...

For the first question, is the purpose that piperidine acts as the base and helps form the enolate ion intermediate? Can you explain why it would not work as efficiently without it? For the second question, I know that the hydrogen that is most acidic is between the two carbon-oxygen double bonds, can you show to me why that is via resonance? For the last question, is it because the amino group is tertiary? Thank you so much in advance!