Answer:
francium
Explanation:
The most expensive natural element is francium, but it decays so quickly it can't be collected to be sold. 
 
        
             
        
        
        
The Coriolis force bends the air current.
Explanation:
- Coriolis force is an inertial force that opposes or deflects the motion of a freely moving mass from its original path.
- The Deflection of wind and ocean current on Earth are all the effect of coriolis force.
- Such an effect is termed as Coriolis effect.
- Coriolis force act to a particular point of reference and not beyond that.
 
        
                    
             
        
        
        
Answer:
D) It is a measure of distance.
Explanation:
I belive is the answer