Answer:
I will explain the concept of magnetic field and how it can be calculated.
Explanation:
The formula for magnetic field at the center of a loop is given as
B = μ
I / 2R
where B is the magnetic field
R is the radius of the loop
I is the current
and μ is the magnetic permeability of free space which is a constant 4π × 
newtons/ampere²
If the magnetic field at the center of the loop is 0, then μI = 0
I = 0 which means there will be no current flow in the loop.
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.
