document.write( "Question 992225: if a projectile is shot vertically upward from the ground with an initial velocity of 150 ft per sec. Neglecting air resistance, its height S (in feet) above the ground t seconds after projection is given by S=-16t^2 + 150t\r \n" );
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document.write( "after how many seconds will it be 60ft above the ground? \n" );
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