IV. Weighted-Average Number of Shares On January 1, 2020, Warden Company had 300,000 shares of common stock outstanding. During 2020, Warden had the following transactions that affected the common stock account. January 1 March 1 August 1 October 1 Instructions: Issued 80,000 shares Issued a 2-for-1 (2:1) stock split Acquired 40,000 shares of treasury stock Reissued 10,000 shares of treasury stock Determine the weighted-average number of shares outstanding as of December 31, 2020.