B.)<span>A doctor would use technetium-99m because a short half-life indicates a quick measurement, and a geologist would use rubidium-87 because a longer half-life means that there is a longer time to measure old rock. </span>
*Warning* This is an educated guess
I would go with point B because it is at the lowest point on the map. Water always travels down, meaning, if no obstructions, it would travel to the ground closest to the Earth's center.
Hope this helps!
The mouth
Amongst the most vital areas to protect are the neck, face and mouth. Though keeping a set of tiger whites will be most people’s primary concern the gum and mouth guards of today also help reduce the risk of concussions and tongue injuries resulting from impacts to the jaw. The most common mouth guards available are “boil and bite” types. These are heated in order to be moulded around the user’s teeth and then form a more resistant solid on cooling. Their main component is poly(ethylene-vinyl acetate) or PEVA, made from the polymerisation of ethene with vinyl acetate.
the synthesis of PEVA by radical polymerisation
