Explanation
To reach the correct answer, follow the steps below:

1) Drag Category, and sub-category to the row shelf. Drag Profit to the Column shelf
2) Click the Sort-ascending icon as shown above, to sort the profits from least to greatest as shown:
Click the 'Show mark labels icon'

As we can see, Fasteners has the least Profit in the Office Supplies Category, and hence is our correct answer!

Explanation
You can create a group to combine related members in a field. The icon associated with a group is a paper clip!

Explanation
As the names suggest, if we subtract the order date from the shipping date, we simply get the number of days between these 2 dates.
We can these use this calculated field in our charts, and can use COUNT, SUM, AVG etc with them according to our need.

Explanation
To assign a color to marks in the view, do the following:
From the Data pane, drag a field to Color on the Marks card.
Tableau applies different colors to marks based on the field's values and members. For example, if you drop a discrete field (a blue field), such as Category, on Color, the marks in the view are broken out by category, and each category is assigned a color.

If you drop a continuous field, such as SUM(sales), on Color, each mark in the view is colored based on its sales value.

Explanation
View Data allows you to inspect your data in a spreadsheet-like layout. You can view data either for the data source as a whole, or to see the underlying data for an individual mark or a group of marks. In a worksheet, the rows that you see in the View Data window are always scoped to the current selection or the current view.
The View Data window displays as much of the data as possible by default, up to 10,000 rows. Field names are shown as column headers and can be dragged and dropped to change their display order. Click a column header to sort the values in that column.
From the official website: