the length of shadow of vertical pole of height h thrown by the sun's Ray's at three different movements are h,2h,3h.the sum of the angles of elevation of Ray's at these three moments is equal to

Question : If the length of the shadow of a vertical pole is $\sqrt{3}$ times the height of the pole, the angle of elevation of the sun is:

Option 1: $60°$

Option 2: $45°$

Option 3: $30°$

Option 4: $90°$

Question : The length of the shadow of a vertical pole on the ground is 36 m. If the angle of elevation of the sun at that time is $\theta$. Such that $\sec \theta=\frac{13}{12}$, then what is the height (in m) of the pole?

Option 1: 12

Option 2: 15

Option 3: 18

Option 4: 9

Question : The length of the shadow of a vertical pole on the ground is 18 m. If the angle of elevation of the sun at that time is $\theta$, such that $\cos \theta=\frac{12}{13}$, then what is the height (in m) of the pole?

Option 1: 7.5

Option 2: 9

Option 3: 18

Option 4: 12

Question : The angle of elevation of the sun changes from 30° to 45°. The length of the shadow of a pole decreases by 4 metres and the height of the pole is: (Assume $\sqrt3$ = 1.732)

Option 1: 1.464 m

Option 2: 9.464 m

Option 3: 3.648 m

Option 4: 5.464 m