How much is this CD? / Quanto custa esse CD?
It’s five dollar and twenty-five cents. / São cinco reais e 25 centavos.

How much are these pencils? / Quanto custa esses lápis?
They’re two dollar and seventy cents. / São dois reais e 60 centavos.

–Se usa “How much is this…” quando é singular, quando é plural usa-se “How much are these…” .