Answer:
I just finished a unit on Scientific Method in my science class! Anyway, it's defined in the screenshots below. Hope this helps!
It is for safety if you come to a sudden stop like newtons law say if an object is in motion it stays in motion until a force stops it if the bike suddenly stopped then you would fly off because you wold still be going. and the gear helps protect you.
Volume of solute = 250 * 2%
= 250 * 0.02
= 5
In short, Your Answer would be 5 mL
Hope this helps!
B protons are positive atoms and are inside the nucleus