Krypton is the least metallic. Because it is a noble gas. The elements go from left to right in order of most to least metallic. Krypton is the farthest right out of all of the elements you listed.
The copper needed to be heated and manipulated (or shaped)
A projectile has some form of thrust to propel it in the desired direction, while an object in free fall has no extra force guiding/propelling it
They would identify the frogs by looking at their DNA and the genetic material
