秦汉时期已经开始发展铁器成型技术，这句翻译为（ ） A: Iron casting technology has already been employed in Qin (220 to 205 BC) and Han dynasties (206 –220 BC). B: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (236 –210 BC). C: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (202 –220 BC). D: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (201 –227 BC).

‍秦汉时期已经开始发展铁器成型技术，这句翻译为（ ）‌ A: Iron casting technology has already been employed in Qin (220 to 205 BC) and Han dynasties (206 –220 BC). B: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (236 –210 BC). C: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (202 –220 BC). D: Iron casting technology has already been employed in Qin (221 to 207 BC) and Han dynasties (201 –227 BC).

给出如下代码:>;>;>; x = 2>;>;>;eval("x *2+1")上述代码的输出结果是()。 A: 5 B: 系统报错 C: x *2+1 D: 221

‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬给出如下代码：‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬＞＞＞ x = 2＞＞＞ eval("x *2+1")上述代码的输出结果是‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬( )。‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬ A: 221 B: x *2+1 C: 5 D: 系统报错

设矩阵三阶A=（41-2,221,31-1）,B=（1-3,22,3-1）,求X使得AX=B

三国魏、蜀、吴三国成立的时间？（） A: 221；220；222 B: 220；221；222 C: 220；222；221 D: 222；220；221

( 207 )8=(________)10

春秋战国时期大约是公元前（）年之间。 A: 841—770 B: 770—450 C: 450—221 D: 770—221

秦统一六国的时间是什么（ ） A: 公元前840 B: 公元前335 C: 公元前221 D: 公元221

战国经历的时期大约是公元前（）年之间。 A: 841—450 B: 1046—841 C: 450—221 D: 221—180