按《岩土工程勘察规范》(GB 50021—2001)，砂土(粉砂)和粉土的分类界限是 ()。
A. 粒径大于0.075mm的颗粒质量超过总质量50%的为粉砂，不足50%且塑性指数Ip≤10的为粉土
B. 粒径大于0.075mm的颗粒质量超过总质量50%的为粉砂，不足50%且塑性指数Ip＞3的为粉土
C. 粒径大于0.1mm的颗粒质量小于总质量75%的为粉砂，不足75%且塑性指数 Ip＞3的为粉土
D. 粒径大于0.1mm的颗粒质量小于总质量75%的为粉砂，不足75%且塑性指数 Ip＞7的为粉土
What is the best title for this newspaper article？ ______.
A. The Story of Mr. Johnson, A Sweet Salesman.
B. Car Boot Can Serve As The Best Escape Route.
C. Driver Escapes Through Car Boot.
D. The Driver Survived A Terrible Car Accident.
Balbir wants to guide a robot along the white squares through this maze. The robot starts
A. FORWARD 4, TURN LEFT 90°, FORWARD 2, TURN RIGHT 90°, FORWARD 3, TURN RIGHT 90°, FORWARD 5.
B. FORWARD 3, TURN RIGHT 90°, FORWARD 1, TURN RIGHT 90°, FORWARD 3, TURN LEFT 90°, FORWARD 3.
C. FORWARD 3, TURN LEFT 90°, FORWARD 1, TURN RIGHT 90°, FORWARD 2, TURN RIGHT 90°, FORWARD 4.
D. FORWARD 3, TURN RIGHT 90°, FORWARD 1, TURN LEFT 90°, FORWARD 2, TURN LEFT 90°, FORWARD 4.
微信支付 
支付宝支付