(1)由二次根式有意义得:a+2≥0,
解得a≥-2;
(2)由二次根式有意义得:3-a≥0,
解得a≤3.
As he reached ______ front door, Jack saw ______ strange sight.
A.the, /
B.a, the
C./, a
D.the, a
按基础的构造形式分类,可将基础分为( )。
A.无筋扩展基础
B.扩展基础
C.条形基础
D.井格式基础
E.箱形基础