Question

4. The contents of the layer can be
hidden or shown by clicking on
which icon before a layers
thumbnail.​

Answer 1

Explanation:

Hold down "Alt" (Win) / "Option" (Mac) and click on the Layer Visibility icon to temporarily hide all the other layers. To turn all the layers back on again, hold down Alt (Win) / Option (Mac) and click again on the same Layer Visibility icon.