'An old proverb says that something can be as dull as this bluish-gray element, symbol Pb'
lead
HOW DULL!: An old proverb says that something can be as dull as this bluish-gray element, symbol Pb
An old proverb says that something can be as dull as this bluish-gray element, symbol Pb
An old proverb says that something can be as dull as this bluish-gray element, symbol Pb
HOW DULL!
lead
HOW DULL!