22. In an air-filled parallel-plate waveguide with dimension a = 4 cm, according to the expression of electric field distribution,
E= E0(sin25πx+3sin50πx)sin(8x109πt)
What is the value of phase constantβ2 of propagation wave?
(A) 7.5
(B) 23.5
(C) 29.2
(D) 74 radm
3. Consider the physical processes in the Hadley circulation. (total 25 points]