题目

Back in March, the COVID-19 virus had just started its deadly journey across the country. People were___ 1 ___ about shortages of just about every staple of daily life, and Jonny Blue__ 2 ____ on one particularly urgent need. Blue, a 33-year-old physician from Encinitas, California, saw reports of people___ 3 ____ toilet paper. He came up with a___ 4 ____ but brilliant solution. One Saturday morning, Blue put up a sign, which_____ 5 _____ “Share Your Toilet Paper”, and camped out on the corner of ElCamino Real and Encinitas Boulevard. “It just_____ 6 _____ me to remind people, liste阅读以下短文，然后解决下列问题：如果一个三角形和一个矩形满足条件：三角形的一边与矩形的一边重合，且三角形的这边所对的顶点在矩形这边的对边上，则称这样的矩形为三角形的“友好矩形”。如图（1）所示，矩形ABEF即为△ABC的“友好矩形”。显然，当△ABC是钝角三角形时，其“友好矩形”只有一个。1.仿照以上叙述，说明什么是一个三角形的“友好平行四边形”2.如图（2），若△ABC为直角三角形，且∠C=90°，在图（2）中画出△ABC的所有“友好矩形”，并比较这些矩形面积的大小；3.若△ABC是锐角三角形，且BC>AC>AB，在图（3）中画出△ABC的所有“友好矩形”，指出其中周长最大的矩形。（标上字母）