Light: Activity 2:

This picture is being hit by a single light, but the photographer is using a reflector which makes the picture more bright and lit up.
(Photograph by: David Peterson)

This photo uses multiple light sources. We know this because the first light is allowing her left side be lit and another camera is allowing the right side be lit and creates a shadow. Bonus, for showing rule of thirds! (photo by: Mark Stagi)

Light: Activity 3:

This photographer used light in this photograph. You can see they shadow on the side of her face. The photographer probably used a light meter because it would be easier not to over expose or underexpose the women's face. (Photographer:Julia Gibson)

Obviously the same model, but totally different lighting. This photographer made this model's face more dark with lighting. He also, used a light meter to make sure he got this effect. it makes the photograph more darker and the right side is getting more light and there a small shadow in the back. (Photograher: Kenny Gee)

Light: Activity 4:

 This is an example of DEEP depth of field because  the background and foreground are in focus. This photographer used an aperture of f/18. So the bigger the aperture is grater depth of field.
(Photo found at: www.history.com)

This is an example of DEEP depth of field because all the boats focused and the background is clear. This photographer probably used a large aperture size.
(Photo found at: www.photo.stackexchange.com)

This is an example of shallow depth of field because some of the keys are focused and the rest is blurred out or not focus.
(Photo found at: www.colourbox.com)

This is an example of shallow depth of field because the main focus is the dandelion and the background isn't distracting.
(Photo found at: www.footage.shutterstock.com)