PI is called isoelectric point at which the amino acid is present as as Zwitter ion which contain equal positive and negative charges so the net charge on this amino acid will be Zero (Neutral)
Explanation: boron needs 4 electron to obtain octet and Fluorine has just one. For the valence shell to be completely filled it will have to form BF4- with 4 fluorine atom surrounding it.
Because speed is a scalar quantity which he has only magnitude and no direction while velocity is a vector quantity because it has both magnitude and direction.
