Four parts of an experimental design

1) this sin't a search engine. It's a question and answer site.

2) we don't do your homework for you. And this sounds like a homework question. If it's not, than please elaborate.

Here's the search engine results: Google (http://www.google.com/#hl=en&sugexp=ldymls&xhr=t&q=four+parts+of+an+experimental+design&cp=0&qe=Zm91ciBwYXJ0cyBvZiBhbiBleHBlcmltZW50YWwgZGVzaWd u&qesig=0I8J8vizuAozxQuxtigR4Q&pkc=AFgZ2tlhn5JdBrg3gei5dp1_nRYLSu0q7ASrFZbfayQ7KJ 8lPh9R5xiQRCuzqucLKh-wdv8XvPXgpCp4Jn4swFlOCGCYABrKNA&pf=p&sclient=psy&site=&source=hp&aq=f&aqi=&aql=&oq=four+parts+of+an+experimental+design&pbx=1&fp=25a0b2344dc0e416)