Which phenomena can be explained by the wave nature of light?

If $L$ is the coherence length and $c$ is the velocity of light,the coherence time is

Two coherent sources of intensity ratio $9:4$ produce interference. The intensity ratio of maxima and minima of the interference pattern is

The wave nature of light is verified by

The interference pattern is obtained with two coherent light sources of intensity ratio $4:1$. If the ratio $\frac{I_{\max} + I_{\min}}{I_{\max} - I_{\min}}$ is $\frac{5}{x}$,then the value of $x$ will be equal to:

Light exhibits wave nature because...