题目

第四部分：书面表达（共三节，满分30分）  课文填空（共10小题；每小题1分，满分10分） According to the old stories of Iceland and Norway, Eric the Red was f  56   to leave Iceland because he had c  57   a murder, for which he got i  58   trouble. Eric reached Greenland and d  59   that people could live in the place where he l   60  . He returned to Iceland and told people to go back with him to Greenland. Eric set sail once again, this time with 25 ships, of which only 14 made it to Greenland.  As you can see, I did e  61  . I will bring my s如图，在四边形ABCD中，∠ABC=90°，AC=AD，M，N分别为AC，CD的中点，连接BM，MN，BN．（1）求证：BM=MN；（2）若∠BAD=60°，AC平分∠BAD，AC=2，求BN的长．