Answer:
I'm sorry but I'm not doing the whole test
Explanation:
 
        
                    
             
        
        
        
Answer: Air
Explanation: Pure air is a mixture of several gases that are invisible and odorless. Consists of 78% nitrogen, 21% oxygen, and less than 1% of argon, carbon dioxide. 
 
        
             
        
        
        
Answer:
50 ltr 150 ltr
Explanation:
this problem can be solved by the mixture and allegation concept which can be clearly understand from bellow figure in which the concentration of solution 1 is 50% and concentration of solution 2 is 90% before mixing after mixing with help bellow concept the ratio of concentration become 10:30
ratio of solution 1 and solution 2 =10:30
                                                      =1:3
total mixture is 200 liters 
part of solution 1= ×200
 ×200
                            =50 liters
part of solution 2= ×200
 ×200
                            =150 liters
 
        
             
        
        
        
The answer is electrical energy
        
             
        
        
        
Answer:
Hiya! Your answer would be an Electromagnetic Wave. 
Explanation:
Electromagnetic Wave is an electromagnetic wave that travels through space at the speed of light at about 300,000 kilometers per second. So when we talk about light traveling in waves, we can also talk about frequency, or the number of wavelengths that pass a certain point in a given length of time. We usually measure this as the number of wavelength cycles that pass per second. The units for this measurement are Hertz (hz).
So, if the wavelength of a light wave is shorter, that means that the frequency will be higher because one cycle can pass in a shorter amount of time. This means that more cycles can pass by the set point in 1 second. Likewise, a light wave that has a longer wavelength will have a lower frequency because each cycle takes a longer time to complete.
Hope I helped and I hope you get it right! :). Have a lovely day my friend! 
~Bella