Find the area of the surface of the half cylinder startset left parenthesis r comma theta comma z right parenthesis : r equals 4 comma 0 less than or equals theta less than or equals pi comma 0 less than or equals z less than or equals 9 endset using a parametric description of the surface.

Ask your question to the AI advisor

Ai-bot is an expert in any field and is the perfect companion for reliable and useful answers and advice on a variety of topics, including science, history, technology, art, sports, health, culture and more.