A. Give the symbol of the element in the fifth period of the periodic table with five valence electrons. (Express your answer as a chemical symbol)
B. Give the symbol of the element in the fourth period of the periodic table with four 4p electrons. (Express your answer as a chemical symbol)
C. Give the symbol of the element in the fourth period of the periodic table with one 3d electron. (Express your answer as a chemical symbol)
D. Give the symbol of the element in the fifth period of the periodic table with a complete outer shell. (Express your answer as a chemical symbol)