干燥基灰分和收到基全硫的代表符号是A、D、和St，A、r。
参考答案：对
New York _____ second in the production of apples last year, producing 850,000,000 pounds. [ ]
A. formed
B. ranked
C. located
D. produced
在一棵二叉树上第8层的结点数最多是 ______。
A．8
B．16
C．128
D．256
