No.
Yes
The water cycle is without a beginning or an end - as it is a circle. If it needs to have a start and finish (something Mother Nature is oblivious of), let's begin at evaporation from the oceans, ending with rain falling from the clouds to flow as rivers (due to gravity) downhill and returning to the oceans, and so on.
north pole
It has the same starting and ending point.
Amorphous solids have no definite melting point because their particles are arranged randomly. Amorphous solids do not have crystal form or definite melting point.
Yes
A ray does have a definite beginning, it's point, but it goes on forever in the other direction, which is symbolized by an arrow.
The water cycle is without a beginning or an end - as it is a circle. If it needs to have a start and finish (something Mother Nature is oblivious of), let's begin at evaporation from the oceans, ending with rain falling from the clouds to flow as rivers (due to gravity) downhill and returning to the oceans, and so on.
north pole
It has the same starting and ending point.
A ray does have a definite beginning, it's point, but it goes on forever in the other direction, which is symbolized by an arrow.
The begining is the "Source" The ending is the "Mouth"
A line segment is a line that has a point at the beginning and at the ending
A full circle has no end. It is continuous.It has no beginning; therefore, it can have no end point - only as it is drawn.
It has the same starting and ending point.
Fiction is organized with a beginning, a point of no return shortly after, and then a climax/ending.
Only in that igneous rock was the first to form on Earth, over 4 billion years ago.