Not sure what a dimond is but a diamond has no perpendicular lines.
A diamond has two pairs of parallel lines.
A right angle has no parallel lines, but it does have perpendicular lines that meet at right angles.
It need not have any.
There are 20 common points.
A trapezoid has 2 parallel lines. It may or may not have perpendicular lines.
Not sure what a dimond is but a diamond has no perpendicular lines.
A diamond has two pairs of parallel lines.
None but it does have perpendicular lines
Diamonds come in all shapes and sizes, which determine the number of perpendicular lines (assuming you are referring to the edges as the lines) so there is no one number of lines or perpendicular lines on a diamond.
A parallelogram has 2 pairs of parallel lines and in the form of a rectangle it has 2 pairs of parallel lines and 4 perpendicular lines that meet at each of its corners at right angles.
There are 2 sets of parallel lines.
A right angle has no parallel lines, but it does have perpendicular lines that meet at right angles.
It need not have any.
10, A decagon has a maximum of five pairs of perpendicular lines, and a maximum of 5 parallel lines. however, this isn't in black and white it can have no pairs of line either perpendicular or parallel
There are no parallel lines in any triangle but a right angle triangle has perpendicular line that meet each other at 90 degrees.
Construction, engineering, drawing, and architecture all use parallel and perpendicular lines. Other than that, it is an important topic because you are learning how to apply the language and tools of mathematics to an intuitive system. These topics have proven important in the history of human kind and also many before you have shown that by learning about parallel and perpendicular lines, one learns how to use math and logic. It is doubtful that you can make a living off of parallel and perpendicular lines, but if you can't understand parallel and perpendicular lines, then I worry about your future.