Answer:
This has all the answer (Data sheet, graph, answers to the questions, and the summary) :)
Molecules and polyatomic ions are formed by covalent bonds.
Now I can actually edit my answer directly: I'm fairly sure I've got this wrong, and my mind has gone blank for how to do it, if someone could delete this that would be great and I'll think about it and see if I can figure it out!
use the formula
v= u+ at
v is final velocity , u is initial velocity , a is acceleration and t is time
put the values
20 = 0+ a×5
a = 4 m/s²