Is the line for the equation y = 1 horizontal or vertical? what is the slope of this line? select the best answer.

a.)the line is horizontal. the slope is 0.

b.)the line is horizontal. the slope is 1.

c.) the line is vertical. the slope is undefined.

d.) the line is vertical. the slope is 0.

Fill in the blank 1. a rhombus is a rectangle a) always b) sometimes c) never 2. a square is a quadrilateral a) always b) sometimes c) never 3. a trapezoid is a kite a) always b) sometimes c) never 4. a quadrilateral is a kite a) always b) sometimes c) never 5. a square is a rhombus a) always b) sometimes c) never 6. a parallelogram is a rectangle a) always b) sometimes c) never