text: Joachim Low brags a fortunate assault and midfield, one which can invade any group in the opposition on their day, however they are confronting a smaller than normal guarded emergency with first decision focus backs and full backs missing. Mats Hummels is simply recuperating from harm, while Antonio Rudiger has been discounted of the competition. Emre Can, who is basically a cautious midfielder, could wind up at left-back, which will give Ukraine a chance to put weight on the safeguard.
  
  I suppose every reader of this ‘ere blog will know Heron’s formula for the area $latex K$ of a triangle with sides $latex a,b,c$:
  However, I have only recently become aware of Brahmagupta’s formula for the area of a cyclic quadrilateral. A cyclic quadrilateral, if you didn’t know, is a (convex) quadrilateral all of whose points lie on a circle:
  And if the edges have lengths $latex a,b,c,d$ as shown, then the formula states that the area is given by
  This can be seen to be a generalization of Heron’s formula. Although the formula is named for Brahmagupta (598 – 670), who does indeed seem to…
  
  In Singapore, cockroaches are impossible to completely eradicate due to the tropical climate which is ideal for cockroaches. In many other countries, a common method to kill cockroaches is using Boric Acid. Boric acid is considered a natural substance, and is effective at killing cockroaches. It works as a “stomach poison affecting the insects’ metabolism, and the dry powder is abrasive to the insects’ exoskeletons”. As such, it is impossible to develop a “resistance” to boric acid, unlike for insecticides where numerous cockroaches are now immune to insecticides.
  Boric acid is also considered non-toxic, it is similar to table salt in its toxicity level. Boric acid has a “secondary kill” effect: cockroaches who die will be eaten by other cockroaches, leading to a chain reaction of cockroach deaths. Hence, it is more effective than sprays or traps which only kill the cockroach that is targeted.
  However, when one starts to look for boric acid in Singapore, it is quite hard to find it in the pure powder form. Whether it is banned, or is simply not popular, it seems that no one on the internet knows.
  I found a cockroach bait containing Boric Acid in Qoo10 below. It is a Malaysian brand. It is written on the packaging that boric acid is the active ingredient, and I also double confirmed with their Facebook customer service. Here it is:
  Another problem about old HDB estates is the interior rubbish chute. Though very convenient, it is also a direct pathway for cockroaches to enter your home. The solution is to install a new air-tight rubbish chute hopper such that the cockroaches cannot pass through.
  Author mathtuition88Posted on September 28, 2018 September 28, 2018 Categories maths tuitionTags cockroach, pestLeave a comment on Cool Fact: Cockroaches are becoming Endangered/Extinct in Russia (and other post-Soviet states)