Which of the following organs is not a part of the respiratory system? A. Nose
B. Lungs
C. Kidney
D. Trachea

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C

Explanation:

the rest are in the respiratory system.

C. kidney

Explanation:

respiratory system means an organ that helps you to breathe a nose,lungs,trachea are an organ to help you breathe. However, Kidney is not, this is because the kidney is in the urinary system which means to eliminate waste from the body. The urinary system also includes bladder, ureters, urethra.

i think it because equal matrices have equal dimensions, only square matrices can be symmetric. for all indices and . every square diagonal matrix is symmetric, since all off-diagonal elements are zero. in linear algebra, a real symmetric matrix represents a self-adjoint operator over a real inner product space.