Refraction of Light

Q. In the arrangement shown in the figure, the image of the object as seen by the observer is

1. real and inverted
2. real and erect
3. virtual and inverted
4. virtual and erect

Q. A light ray travelling in glass medium is incident on glass-air interface at an angle of incidence $\theta$. The reflected (R) and transmitted (T) intensities, both as function of θ, are plotted. The correct sketch is

1. 
2. 
3. 
4. 

Q. When light is refracted, which of the following does not change?

1. Frequency
2. Velocity
3. Wavelength
4. Amplitude