计算:211×555+445×789+555×789+211×445=______.
计算:123+456+789+987+654+321=______.
计算:123+234+345+456+567+678+789=______.
计算:5002-499×501=______.
计算:1232-122×124=______.
计算:1001×1001-1001=______.
简便计算:101×99=______.
计算:888×999=______.
计算:lg2+lg5=______.
计算:1.996+19.97+199.8=______.
计算5.762-4.242=______.
计算:57.32°=______度______分______秒.
1.计算:(1)211×555+445×789+555×789+211×445 (2)S=1-2+3-4+...+(-1