A student Prepared $20\%$ sodium hydroxide solution in a beaker to study saponification reaction. Some observations related to this are given below
<br>(I) Sodium hydroxide solution turns red litmus blue
<br>(II) Sodium hydroxide readily dissolves in water
<br>(III) The beaker containing solution appears cold when touched from outside
<br>(IV) The blue litmus paper turns red when dipped into the solution The correct observations are :