1. Investigating the effectiveness of natural insecticides on controlling pest
2. Examining the effects of different types of music on human memory and cognitive performance
3. Analyzing the impact of different soil types on plant growth and development
4. Investigating the efficiency of renewable energy sources such as solar, wind or hydro power
5. Studying the effects of different types of exercise on cardiovascular health and fitness
6. Investigating the effectiveness of different water filtration methods on removing contaminant
7. Analyzing the effects of different food preservatives on the shelf life and nutritional quality of fruits and vegetable
8. Examining the relationship between air pollution and respiratory health in urban area