What does calibrating the cabbage pH indicator mean

Which metal exist in liquid state and can be cut with knife ?

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.

When a device is used in a circuit in which the voltage is 81 v the current flowing through the device is 3 a what is the resistance of the device