When you create a story using a file as the data source, you automatically create an embedded dataset. A dataset is a collection of data that is imported into SAP Analytics Cloud and can be used in a story. An embedded dataset is unique to that story and cannot be shared outside the story or refreshed. You can transform or wrangle the data in the dataset to meet your story needs in the Data Preparation area

To improve performance in stories, users should use JPG images instead of PNG images, as JPG images have smaller file sizes and load faster. Users should also minimize the number of linked models in a story, as each linked model adds complexity and increases the loading time. Using unbooked data or exception aggregations does not affect performance in stories. Verified [SAP Analytics Cloud - Performance Optimization]

You can define a calculation for a table in three ways:
Table: You can add a simple calculation by selecting two measures in a table, right-clicking, choosing Add calculation, and choosing the calculation you want. You can also add a repeating or single column or row to a table by right-clicking on a measure or dimension and choosing Add Calculation1.
Calculation editor: You can open the calculation editor from the drop-down menu of Measures or Dimensions in the Designer Panel and create complex calculations for a chart or table. For each type of calculation, a new calculated member is created. You can also use dimension attributes as part of a calculation2.
Story: You can create a calculated measure in the Builder pane of a story. When setting up your calculation, you apply the typical formula functions, conditions, and operators to the data contained in your model. Calculated measures allow you to perform mathematical and Boolean operations on your data1.
1: Calculating Data in Stories - SAP Learning 2: SAP Analytics Cloud In-story Calculation Series - An Introduction

When you create a new story and select a responsive page, you are offered the choice of Optimized or Classic Design Experience. This choice determines the design mode that you will use to create your story. The Optimized Design Experience is the newer and more advanced design option that offers several usability improvements and performance enhancements compared to the Classic Design Experience. However, the Optimized Design Experience also has some limitations and differences, such as the unavailability of some elements that are present in the Classic Design Experience1. Therefore, you should choose the design mode that best suits your needs and preferences. You can also switch between the design modes later, but you may lose some features or formatting in the process2.
1: Choosing Between Optimized and Classic Design Modes - SAP Learning 2: Switching Between Optimized and Classic Design Modes - SAP Learning

The Optimized Design Experience is a new user interface for SAP Analytics Cloud that simplifies and enhances the story design process. The Optimized Design Experience offers some benefits over the Classic Design Experience, such as:
Improved tooltip interactions: You can hover over any data point in a chart to see a tooltip with more information. You can also click on the tooltip to access more actions, such as filtering, drilling, commenting, etc.
Ghost loading indicators: You can see a ghost image of the elements on a page while they are loading. This gives you a preview of the layout and size of the elements before they are fully rendered.
Data Analyzer: You can use Data Analyzer to quickly create ad hoc analysis based on models or datasets. You can also save your analysis as stories or pin them to your home page.
Point of Interest: You can use Point of Interest to highlight a specific data point or area in a chart. You can also add annotations, comments, or links to the Point of Interest.
Time Series chart: You can use Time Series chart to create interactive and animated charts that show how data changes over time. You can also customize the appearance and behavior of the Time Series chart.
Therefore, the correct answer is Improved tooltip interactions and Ghost loading indicators, as they are the benefits of using the Optimized Design Experience. Verified Reference:
: Optimized Design Experience Overview