How many zoom meeting create?

Hi, I will try to develop an app via zoom api.

There are 3 situations.

  1. 1~300 zoom meeting(1:1) is created at the same time. i guess meeting time will spend about 40 minues.
  2. one zoom meeting(1:N) is created. I guess meeting time will spend about 5 hours.
  3. both first situation and second situation at the same time.

[Questions]
Q1. Should i buy just one account(Pro)?

Q2. How many user can i create?

Q3. If can, how can i know who is host(license)?(third situations)

Q4. How many zoom meeting can be created at the same time?(first situations)