Because liquids travel at different speeds through an absorbent paper they can be separated by

Chromatography. It can separate dissolved substances from a mixture. Examples is separating different colors of dyes in a black ball pen ink

The activity series is shown in the attached picture. if the element is below the other, then you can displace the other. following the activity series as a guide, the reactions are as follows: nickel and aluminum chloride3 ni + 2 alcl₃  → 3 nicl₂ + 2 albarium and copper bromideba + cubr  →  no reaction because cu is less oxidizable than bapotassium nitrate and aluminum3 kno₃ + al  → al(no₃)₃ + 3 ksodium phosphate and zincnaso₄ + zn  → znso₄ + na

C) the increase in atmospheric pressure pushes the walls of the balloon outward thus making it  is the answer.hope i you.