The factory last month because it caused too much pollution.
A:closed down
B:fell down
C:hurried up
D:got up
染色体是由____ 和____ 两种物质组成的.DNA是遗传物质,因此可以说染色体就是遗传物质的载体.
0.34×101=____
如图所示.在放大的测力计表盘中画出此时指针位置.