Why do we say that public policies are an improvement hypothesis? Which type of actors can we find in a policy-making process?

Description

Respond to three of these questions in no more than 1000 words (in total):

Why do we say that public policies are an improvement hypothesis?
Which type of actors can we find in a policy-making process?
What are the main differences between the Weberian State, the New Public Management and the Governance models?
What is the policy cycle?
Briefly describe the 3 ways of setting agendas and formulating policy.