Answer: Earth's rotation is slowing slightly with time,thus, a day was shorter in the past. This is due to the tidal effects the Moon has on Earth's rotation. Atomic clocks show that a modern-day is longer by about 1.7 milliseconds than a century ago.
 
        
             
        
        
        
Answer:
Physical Change: 
- Boiling water
- Breaking a pencil
- Water evaporating
- Denting a car door in an accident
- Tearing paper
- Ice melting
- dissolving
Chemical Change:
- Something rusting
- photosynthesis
- metabolism/digestion
- Nuclear power [atoms are arranged differently]
- Smashing paper with two metal balls, burns paper
- Electricity in water, breaks H2O into H2 and O2
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physical change is when there is only physical change occurring--and it can typically be undone easily, 
whereas chemical change is when there is chemical change--which changes the chemical properties of something, which cannot be undone simply. 
hope this helps!!
 
        
                    
             
        
        
        
Answer:
what is microscope is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. 
FUNCTIONS : The microscope is one of the most important tools used in chemistry and biology. This instrument allows a scientist or doctor to magnify an object to look at it in detail. Many types of microscopes exist, allowing different levels of magnification and producing different types of images
 
        
             
        
        
        
Because us humans haven’t explored every inch of the world yet, especially in the deepest parts of the ocean
        
                    
             
        
        
        
The correct answer is option B. Of the following choices given, carbon dioxide is produced during both anaerobic and aerobic respiration. It is the common thing between the two respiration. Anaerobic respiration is the process which do not need oxygen to produce products while the opposite is called aerobic respiration.