我国婚姻法规定“禁止近亲结婚”，其科学依据是（   ）

    Miss Green is very fat and she is very heavy. So she goes to see her doctor. The doctor says, “There isn't anything wrong with you, but you eat too much. I think you must go on a diet. Here's a book for you to read. You must eat the things on page 15. Read it carefully and eat the things for ten days, and then come to me again.”

    Miss Green takes the book home and reads it carefully, and begins her diet.

    Ten days is over now. Miss Green comes to see her doctor again. The doctor finds she is still very fat. So he says, “Do you eat the things on page 15 of that small book now?” “Yes, I do.” Miss Green says. The doctors cannot say anything.

    The next day, the doctor goes to see Miss Green in the afternoon. It is teatime. Miss Green is eating potatoes; “Why are you eating potatoes? They're not in your diet.”

    “But doctor,” Miss Green says, “This is teatime. I eat my diet on breakfast time, lunchtime and suppertime. This diet doesn't tell me anything about my tea.”

已知关于x的方程$\frac{1}{4}{x}^2-\left(m-2\right)x+m^2=0$

（1）若方程有两个相等的实数根，求m的值，并求出此时方程的根；

（2）是否存在正数m，使方程的两个实数根的平方和等于224．若存在，求出满足条件的m的值；若不存在，请说明理由．