Lots of substances. Rocks, metals, minerals, you name it.
        
                    
             
        
        
        
Instability
Explanation:
Isotopes decays because they are unstable. Stable isotopes do not decay. 
- For every atomic nucleus, there is a specific neutron/proton ratio. 
- This ratio ensure that a nuclide is stable. 
- For example, fluorine F, is 10/9 stable. 
- Any nucleus with a neutron/proton combination different from its stability ratio either too many neutrons or too many protons will become unstable. 
- Such nuclide will split into one or more other nuclei with the emission of small particles of matter and considerable amount of energy. 
Learn more: 
Radioactive brainly.com/question/10125168
#learnwithBrainly
 
        
             
        
        
        
Https://www.gstatic.com/education/formulas2/355397047/en/boyle_s_law.svg
        
             
        
        
        
Answer:
false
true
true
Explanation:
false - changing the hypothesis to meet your needs is not a good researcher
true - when you can further analyze and explain then you have a successful experiment even if it's not what you expected
true - successful experiments do not end there. they can lead to more in depth questions.