Britain has promised Rwanda $100m in aid a year over the next decade, with only “light conditionality” (in essence, an understanding Rwanda will not reinvade Congo).
Aren't all membranes semi-permeable? That is, the whole point of a membrane is that it lets some things through and others not. Membranes by definition are permselective or semi-permeable barriers.
First, the solid ice on the surface could have been annealed, meaning that its temperature could have been raised above the 78 Kelvin mark to allow the amorphous ice to recrystallize.
The first could be the case if the product you are selling to these "senior types" is quite pukka, meaning that a barrow boy isn't the right person to sell it.