A fuse is a safety device that stops the flow of electricity when a circuit overheats

Step-by-step explanation:

Slope of a line passing through two points and is given by the formula,

Slope =

Slope of the line PQ passing through the two points P(-8, 2) and Q(4, 2) will be,

Slope '' = = 0

Therefore, slope of the line PQ parallel to the x-axis = 0

Slope of the line MN passing through the points M(8, 6) and N(8, -8) is,

Slope '' = = ∞

Therefore, slope of the line MN parallel to y-axis is undefined.

Since, angle between the x-axis and y-axis is 90°,angle at the intersection  point between the lines parallel to x and y axis will be 90°.

These lines are perpendicular to each other.