PHP exercises

In PHP, define a constant define('HoverTree','He asked', true). The following statement correctly outputs "HoverTree" ( ).

A. echo hovertree;
B. echo Hover Tree;
C. echo 'hovertree';
D. echo 'HoverTree'; hovertree.com/tiku/bjaf/qlnkuqbi.htm

The naming of variables in PHP must start with ( ).

A、#

B、@
C、?
D、$
Answer: http://hovertree.com/tiku/bjaf/phhf3rad.htm

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