密胺树脂可与其他树脂上的羟基、羧基和胺基反应，形成（）结构。
参考答案：交联
A manufacturing firm reports the following in its financial statements: Gross plant and equipment $ 2700000 Depreciation expense$ 235000 Accumulated depreciation $1850000 The average depreciable life of plant and equipment is:
A．
B．
C．
描述交界性肿瘤错误的是（）。
A.形态上属良性
B.常浸润性生长
C.切除后不易复发
D.以手术切除为主
E.切除不彻底易恶变
