The perceived pitch of a tone is largely determined by its * 0 points (A) loudness (B) timbre (C) amplitude (D) complexity (E) frequency 11. Balance is influenced by the * 0 points (A) cochlea (B) basilar membrane (C) eardrum (D) auditory nerve (E) semicircular canals 15. The biological clock that operates in human beings to adjust their functioning to night-and-day periodicity is referred to as * 0 points (A) spontaneous neural activity (B) the biofeedback monitor (C) a fixed-interval schedule (D) a circadian rhythm (E) active consciousness 16. Visual acuity is best in the * 0 points (A) lens (B) iris (C) pupil (D) fovea (E) cornea 18. Which of the following systems produces, circulates, and regulates levels of hormones in the body

E. Frequency

E. Semicircular canals

D. A circadian rhythm

D. Fovea

Endocrine system.

Explanation:

Pitch, in speech, the relative highness or lowness of a tone as perceived by the ear, which depends on the number of vibrations per second produced by the vocal cords ie frequency related scales.

The ear is a sensory organ that picks up sound waves, allowing us to hear. It is also essential to our sense of balance: the organ of balance (the vestibular system) is found inside the inner ear. The vestibule is the region of the inner ear where the semicircular canals converge, close to the cochlea (the hearing organ).

A circadian rhythm is the 24-hour cycle that regulates the timing of processes like eating, sleeping, and temperature. This ensures that there is a periodicity with necessary biological processes.

The area of greatest visual acuity is situated inside the macula called fovea. It has the maximum number of rods responsible for vision.

The endocrine system is a chemical messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs.

i believe the answer would be:

d. violin, clarinet, french horn, and tuba