Question:

(a) Briefly describe open source technologies, outlining the difference between open source technologies and free technologies.

(b) Show advantages of using open source technologies.

(c) Explain how PHP can be used to address the problem of HTTP being stateless.

(d) Explain each of the following string functions below, illustrating your answers with simple examples:

(i) strlen()

(ii) strpos()

(iii) str_replace()

(e) Explain how the most common syntax errors occur in PHP, illustrating your answer with sample codes.