Startups, are your cash reserves in a bank account or invested in liquid assets?

Asking this for a service I am building. Liquid assets would be Treasury bonds, notes, etc. which are safe and produce some returns. For some helpful context, I would greatly appreciate it if you could answer some of the following questions:

1. How much cash reserves do you have and how much runway does this give you? (Feel free to give a range if you don’t want to disclose exact numbers.) 2. Are you concerned about the safety of keeping large amounts of cash in a bank (where it is only insured up to $250k)? 3. How comfortable would you be investing your cash reserves in Treasury bonds and such investments if you don’t already do so?