Which is a characteristic of the PHP language?

An example of a PHP string is:

Functions using global variables must declare the variables by using

Which PHP function sorts an array?

One way to output a string in PHP is:

Which variable is not predefined by PHP?

Which is not correct?

Which would produce an error: $currentDT=new DateTime();

Which is not a Super Global variable in PHP?

Which will decode a JSON variable $json to an object? $json = '{'abc':1,'def':2,'ghi':3,'jkl':4,'mno':5}';

What would be the output of the I and II sample codes: I) $a = array(); $b = $a; $b['foo'] = 42; echo $a['foo']; II) $a = new StdClass(); $b = $a; $b->foo = 42; echo $a->foo;