Tango Corporation, a calendar year taxpayer, has been an S corporation for several years. Tango's business activities have become very profitable in recent years. On June 16, 2019, its sole shareholder desires to revoke the S election.

a. How does Tango revoke its S election? When does the revocation take effect?

b. Assume Tango files a prospective revocation effective July I, 2019. What tax returns are required of Tango for 2019? For 2020? When are these returns due?

c. If the corporation makes a new S election after the revocation, when does it take effect?