1 gallon = 231 cubic inches
1 cubic foot = 1728 cubic inches
                       (55 gal) x (231 in³/gal) x (1 ft³/1728 in³)
                   =    (55 x 231 / 1728)  ft³
                   =         7.352 cubic feet       (rounded)  
        
             
        
        
        
Answer;
-The rocks are the same age 
Explanation;
Seafloor spreading is the process by which the seafloor moves apart at mid-ocean ridges.  Divergent seafloor spreading occurs at this type of plate boundary.
Seafloor spreading and other tectonic activity processes are the result of mantle convection. Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. 
 
        
             
        
        
        
B. five electrons
If you want an explanation, here it is.
The atomic number gives the number of protons. Protons which have a positive charge are balanced by an equal number of electrons in a neutral atom. Boron number 5 has five protons and therefore as a neutral atom also has five electrons.
        
                    
             
        
        
        
Answer:
They are the only joints that can do 360 degrees and rotate with their own axis. But, because of its free-moving, it is prone to any dislocation compared to other movable joints.
Explanation: