Q: through which of the following ways can heat be transferred?
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a. by direct or indirect contact between objects at different temperatures.
b. only by direct contact between objects at different temperatures.
c. only by indirect contact between objects at different temperatures.
d. heat can never be transferred between objects.

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.

he made 11 calls in one day

the answer is a. hope this .