2015:
The induced emf produced in the rod is given by $\epsilon = Blv$.
2016:
The induced emf in the coil is given by $\epsilon = \frac{d\phi}{dt}$, where $\phi$ is the magnetic flux. The magnetic flux is given by $\phi = BA$, where $A$ is the area of the coil.
If the magnetic field is changed to $\frac{3B}{2}$, the magnetic flux will increase by a factor of $\frac{3B}{2B} = \frac{3}{2}$. Therefore, the induced emf will increase by a factor of $\frac{3}{2}$.
If the magnetic field is changed to $\frac{B}{2}$, the magnetic flux will decrease by a factor of $\frac{B}{2B} = \frac{1}{2}$. Therefore, the induced emf will decrease by a factor of $\frac{1}{2}$.
2017:
The induced emf in the loop is given by $\epsilon = \frac{d\phi}{dt}$, where $\phi$
