Got it. Whenever we come across a dead marker, we throw the board away and get a blackboard instead!
About that, could we have a similar article on blackboards and chalk? All I know is that there was much ado [0,1,2] about a certain Japanese manufacturer shutting down a couple of years ago. They, allegedly, made the best chalk and prices on the secondary market rose high after the news came out.
About that, could we have a similar article on blackboards and chalk? All I know is that there was much ado [0,1,2] about a certain Japanese manufacturer shutting down a couple of years ago. They, allegedly, made the best chalk and prices on the secondary market rose high after the news came out.
[0] https://www.reddit.com/r/math/comments/3a05u3/why_mathematic... [1] https://www.reddit.com/r/math/comments/3axqxe/hagoromo_presi... [2] https://www.reddit.com/r/math/comments/3rciv0/an_update_on_w...