A 40 kg dog is sitting on top of a hillside and has a potential energy of 1,568 J. What is the height of the hillside? (Formula: PE = mgh) 3.9 m
4.0 m
39.2 m
40.0 m

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.

c)as speed changes, wavelength and frequency change.

everything changes!

not too sure thinking all accelerations are pointed down