Answer:
supaya tak meletup
Explanation:
sebab hitam dapat menghalang cahaya matahari daripada kena ke tabung didih agar tidak terlebih panas dan menyebabkan letupan
 
        
             
        
        
        
The term is normally applied to a group of between six and nine elements (boron, silicon, germanium, arsenic, antimony, tellurium, and possibly bismuth, polonium, astatine) found near the center of the P-block or main block of the periodic table.
        
             
        
        
        
Lysosomes break down waste and other material inside of cells
        
             
        
        
        
For photosynthesis to occur plants need sunlight water and carbon dioxide and chlorophyll. Through the process of photosynthesis plants cover light energy into chemical energy they use this energy to make food which they store as sugars