Answer the following questions related to lines that are parallel to the coordinate axes.
a. (i) Define a vertical line in the Cartesian plane.
b. (ii) State the general equation of any vertical line.
c. (iii) Define a horizontal line in the Cartesian plane.
d. (iv) Write the equation of the vertical line that passes through x=−4.
e. (v) Write the equation of the horizontal line that passes through y=7.