With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Mariah Carey has signature use of the highest register of the human understanding.
text_B: The whistle register -LRB- also called the flute register or whistle tone -RRB- is the highest register of the human voice , lying above the modal register and falsetto register .. register. vocal registration. human voice. human voice. modal register. modal register. falsetto register. falsetto register. whistle. whistle. This register has a specific physiological production that is different from the other registers , and is so called because the timbre of the notes that are produced from this register is similar to that of a whistle .. register. vocal registration. timbre. timbre. whistle. whistle. In some sopranos , the modal register vocal production may extend into what is usually thought of as the whistle register .. register. vocal registration. modal register. modal register. whistle. whistle. With proper vocal training , it is possible for women within all voice types to develop this part of the voice .. voice types. voice types. However , some women are unable to phonate or comfortably produce sound in this register .. register. vocal registration. phonate. phonate. Children can also phonate in the whistle register and , rarely , some men .. register. vocal registration. whistle. whistle. phonate. phonate
related.