All fixed, I think you got me in the middle of sorting the links out
As for the duck, the question having been asked I of course then had to try and work it out...
Using
this paper , a mallard comes out at about 1.876 litres (that is, 0.001876 cubic metres) in volume, and 1.28 kilos in weight. Its gravitation force downwards (gravity times mass) is thus about 12.59N, upwards (volume times water density times gravity) is about 18.4 N. If we assume that, albeit weighted down, we can afford to get it to about 17.4N downwards before it has too much trouble (above 18.4 is where it should sink), then we can reverse the calculation and divide that 17.4 by gravity (of 9.81) to work out the maximum mass of duck possible, which comes to about 1.75 kilos. In other words, a duck actually should be able to wear nearly half a kilo of armour in theory. Given that Wiki tells me a plate armour suit
weighs around 20kg for a 60-70kg human, I think you could probably keep the ratio the same and scale that down and make one that was 0.4kg for a 1.2kg duck. It might not be a very happy duck, but physics suggests it should still be a floating one