CARES ACT (IRA Withdrawal and Re-Deposit within 3-years)

Under the new CARES Act there appear to be rules that allow up to a $100K withdrawal from an IRA for COVID-19 impacts.  My questions are;

1) What is the definition of COVID-19 impacts

2) What will the mechanics be for redepositing the withdrawal within 3 years since this would go over several tax years

3) Do these rules apply to the 401K style TSP where I could withdraw from the TSP and re-deposit into a traditional IRA.  Again, what would the mechanics be if done over several tax years

4) My spouse and I own a Vanguard Variable Deferred Annuity account.  Can I withdraw from this type of insurance account and within 3 years redeposit into a traditional IRA, and what are the mechanics

 

Thanks in advance for any insight on what appears to become a complex tax situation.  dofdear aka BillyBob