Answer:
Because alkali metals are so reactive, they are found in nature only in combination with other elements. They often combine with group 17 elements, which are very “eager” to gain an electron.
Explanation:
hope this helps you if it does please mark brainliest 
 
        
             
        
        
        
The Answer that makes the most sense is C.
        
                    
             
        
        
        
Answer:
पत्र- अपने क्षेत्र की सड़कों की बुरी दशा की जानकारी देते हुए और उन्हें ठीक कराने की प्रार्थना करते हुए नगर निगम अधिकारी को पत्र लिखिए |
 
        
             
        
        
        
the upward force is from the table and the downward is from gravity they are equal in force so the box doesn't fly up or sink down 
 
        
                    
             
        
        
        
since child is moving along with the wagon and we need to find the acceleration of child inside that wagon then in this case the system of interest must be child + wagon
System of interest will be the system that is used to find the force or acceleration using Newton's law
Here we have to assume that system on which if we will calculate the forces then the net value of force on that system will help to calculate the unknown quantities
So here our system will be boy + wagon