If you are talking about arks for construction, the answer would be "The point or line at which an arch or vault begins to curve".
Answer:
The contemporary sport of ice hockey was developed in Canada, most notably in Montreal, where the first indoor hockey game was played on March 3, 1875. Some characteristics of that game, such as the length of the ice rink and the use of a puck, have been retained to this day.
The answer is b cause it’s b