Which quantity and unit are incorrectly paired?
a. quantity: f unit: kg m/s
b. quantity: j unit: n·s
c. quantity: w unit: j
d. quantity: p unit: w
e. quantity: e unit: kg m2/s2

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.