No, a circle can't be a parallelogram. A circle is a curve. A parallelogram is a quadrilateral with two pairs of parallel sides constructed with four line segments. The line segments are straight, and the circle is a continuous curve.
Do you mean, like, the Earth? The equator. If you mean the line going from side to side across the middle of a circle then... the diameter of a circle
infinite
A pair of parallel lines, an ellipse or a circle.
Pair of radii
No, parallel lines are straight lines.
None.
lines of latitude
a semi - circle has zero parallel lines
No, a circle can't be a parallelogram. A circle is a curve. A parallelogram is a quadrilateral with two pairs of parallel sides constructed with four line segments. The line segments are straight, and the circle is a continuous curve.
Do you mean, like, the Earth? The equator. If you mean the line going from side to side across the middle of a circle then... the diameter of a circle
The two points on exactly opposite sides of a circle are parallel to each other. This can be evidenced by finding the derivative/gradient at those points; if they are the same then the two line segments described by those points are parallel.
infinite
A circle.
A pair of parallel lines, an ellipse or a circle.
Pair of radii
You place a ruler on a piece of paper and trace both sides. Put the point of your pair of compasses on the line and draw a circle. Then draw another circle, that is the same size, the same way further along the line. You will then be able to use your rule to draw a line that is a tangent to the two circle, and so parallel to your first line. Once you have done this you will realize that you don't need to draw a full circle just a small arc.