Answer
(a) false
(b) true
(c) true
Work Step by Step
(a) The given statement is false. We cannot know the number of protons by knowing the number of protons of an element because there may be isotopes of the element which have different numbers of neutrons as compared to protons. For example, Hydrogen has three isotopes which all have same number of protons i.e one but different number of protons.
(b) The given statement is true because in a neutral element the number of protons is equal to the number of electrons.
(c) The given statement is true because all the atoms of the same element have same number of protons and number of protons means atomic number. Thus by knowing atomic number, we can find the name of the element.