How do you make the rulers default to pixels instead of inches?

If you apply the Threshold adjustment to an image, what is the result?

Which features allows the browsing and preview of every filter?

The Eraser Tool can be used to:

Which file format natively supports animated frames in all web browsers?

The History window:

'Merge Down' merges selected layer with the layer below it.

For 'Creating Type' you need to add a new layer in the layer palette.

'RGB color mode' stand for?

The 'Magnetic lasso tool' is especially useful for quickly selecting objects with complex edges set against high-contrast backgrounds.

Which will be most suitable for resizing and resampling images for printed or online display.