(2009, Ezhou) The square of the equation kx about x +(k+2)x+k/4=0 has two unequal real roots.

(1) Find the value range of k?

(2) Is there a real number k that makes the reciprocal sum of the two real number roots of the equation equal to 0? If it exists, find the value of k; If it does not exist, explain why.

2. (Zhanjiang, Guangdong, 20 10) The patient took a certain drug according to the prescribed dose, and the blood content per milliliter reached the maximum of 4 mg 2 hours after taking the drug. It is known that the content of Y (mg) per milliliter of blood 2 hours ago is directly proportional to the time x (hours) after taking the medicine. After 2 hours, y is inversely proportional to x (as shown). Answer the following questions based on the above information:

(1). Find the functional relationship between y and x when 20≤≤x;

(2) If 2> is X, the functional relationship between Y and X;

(3) If the treatment is effective when the blood content per milliliter is not less than 2mg, take the medicine once. How long is the effective time to treat the disease?