Build a filter.
Dig water from the ground
        
             
        
        
        
Answer:
1. the electromagnetic wave.
Explanation:
Mathematically, 
wavelength = velocity ÷ frequency
A mechanical wave is a wave that is not capable of transmitting its energy through a vacuum. Mechanical waves require a medium in order to transport their energy from one location to another. A sound wave is an example of a mechanical wave. Sound waves are incapable of traveling through a vacuum.
Electromagnetic waves of different frequency are called by different names since they have different sources and effects on matter, increasing frequency decreases wavelength.
Sound waves (which obviously travel at the speed of sound) are much slower than electromagnetic waves (which travel at the speed of light.)  
Electromagnetic waves are much faster than sound waves and If the Velocity of the wave increases and the frequency is constant, the wavelength also increases.
 
        
             
        
        
        
Answer:
friction help to slow motion in other word it oppose motion, but in a frictionless environment object would move with difficult stopping point.
 
        
                    
             
        
        
        
Answer:
1 hour and 25 minutes
Explanation:
hopefully this helps ,, but like WHY phineas and ferb hshjdshjdhdhdbd im so childish
 
        
             
        
        
        
This means that two objects will reach the ground at the same time if they are dropped simultaneously from the same height. ... When air resistance plays a role, the shape of the object becomes important. In air, a feather and a ball do not fall at the same rate.