Developing Mobile Apps

StackPanel is a simple layout panel that arranges its child elements into a single line that can be oriented horizontally or vertically. StackPanel controls are typically used in scenarios where you want to arrange a small subsection of the UI on your page.
The following XAML shows how to create a vertical StackPanel of items.

XAML -
<StackPanel>
<Rectangle Fill="Red" Height="44"/>
<Rectangle Fill="Blue" Height="44"/>
<Rectangle Fill="Green" Height="44"/>
<Rectangle Fill="Orange" Height="44"/>
</StackPanel>
The result looks like this.

Reference: https://docs.microsoft.com/en-us/windows/uwp/layout/layout-panels Explanation

A split view control has an expandable/collapsible pane and a content area.
Here is an example of the Microsoft Edge app using SplitView to show its Hub.

Reference: https://docs.microsoft.com/en-us/windows/uwp/controls-and-patterns/split-view Explanation

From scenario:
Each item in the past must be linked to the next item in the future.

Users must be able to scroll from past events to future events or from future events to past events.

The app must only allow one level of detail to be linked to each item in the timeline.

Here we can use a hierarchy with each parent node having only one single child node.
Hierarchical structures are good for organizing complex content that spans lots of pages or when pages should be viewed in a particular order. The downside is that hierarchical pages introduce some navigation overhead: the deeper the structure, the more clicks it takes for users to get from page to page.
We recommend a hiearchical structure when:
You expect the user to traverse the pages in a specific order. Arrange the hierarchy to enforce that order.
There is a clear parent-child relationship between one of the pages and the other pages in the group.
There are more than 7 pages in the group.
When there are more than 7 pages in the group, it might be difficult for users to understand how the pages are unique or to understand their current location within the group. If you don't think that's an issue for your app, go ahead and make the pages peers
Reference: https://docs.microsoft.com/en-us/windows/uwp/layout/navigation-basics Explanation

From scenario: All code and markup must conform to the following style guidelines:
Use resource dictionaries for styles that are used more than once.

Use built-in properties of existing panels instead of using separate style objects.

XAML resources are objects that are referenced from markup more than once. Resources are defined in a ResourceDictionary, typically in a separate file or at the top of the markup page. In this scenario the ResourceDictionary is defined in the ResourceDictionery.xaml file.
You access members of the resource dictionary like any other dictionary.
Reference: https://docs.microsoft.com/en-us/windows/uwp/controls-and-patterns/resourcedictionary-and-xaml-resource-references Explanation