A certain electronic memory game is played by answering equations as they fall from the top of the screen in the form of raindrops. Equations fall from the screen at a rate of one every two seconds for the first minute, one every 1.5 seconds for the second minute, and one every second for the third minute. What is the minimum number of questions Danjie must answer correctly in the third minute in order to beat her previous high score?

(1) Danjie’s previous high score was reached by answering all the questions given in the first three minutes and getting 90% of them correct.
(2) If Danjie does not answer 100% of the questions correctly during the first minute and during the second minute, the game will not continue.


[spoiler]OA=A[/spoiler]

Source: Veritas Prep