题目

Dear Zhang Hua, Have you ever been to Thailand? It is a country in Southeast Asia. I’ve been in Thailand for a few days with my parents. We are here for a holiday. Now we are staying in Bangkok (曼谷). It is the capital of Thailand and it is a very interesting place to visit. Yesterday we visited some places of interest in the city. They are great! This morning we went shopping. Bangkok is a wonderful place to shop for jewelry (珠宝) and clothes. My mother bought a nice necklace (项链). My father and I bought some fashionable T-shirts. Thailand is called “Land of Smiles” because pe如图，三角形ABC．（1）量出∠A的度数，∠A= °．（2）过B点作AC边上的高．（3）以AB、AC为邻边作一个平行四边形．（4）三角形ABC的面积与所作的平行四边形的面积有什么关系？请说明理由．