Geothermal corporation issued a press release before the stock market opened announcing that its earnings set a record for the biggest loss the company every had. Explain how each of the following individual scenarios could be consistent with the semi-strong form of market efficiency.

(a) When trading opened after the announcement, the stock price quickly increased by 10%.

(b) The stock price of Geothermal decreased slowly over the 30 days before the announcement.

(c) The stock price decreased by 10% immediately following the announcement but then increased throughout the day so that the closing price was only 2% below the previous day.

(d) The stock price of Geothermal did not change after the announcement was made public