What do you mean by Energy of Simple Hormonic Motion?

A particle on a speing executes shm when the particle is found at x=xmax/2 the speed of the partcle is 

A)vx=vmax 

B)vx=√3vmax/2

C)vx=√2vmax/2

D)vx=vmax/2

displacement associated with three dimensional wave is given by sai x y is equal to 1 + 1 by 2 x + root 3 by 2 k x minus omega t show that the wave propagates along a direction making an angle 60 degree with the x-axis

What is mean by motion and time define it's all types with there parts and their s.i. units.

explain the effects of doppler effect in satellite communication