Answer:
an error message
Explanation:
The return value is the value which is sent back by the function to a place in the code from where the 
was called from. Its main work is to return a value form the function.
In the context, the form of "(symbol-length? 'James)" in Scheme will return the value --- ' an error message'.
Answer: WIREFRAME
A website wireframe, also known as a page schematic or screen blueprint, is a visual guide that represents the skeletal framework of a website.[1]:166 Wireframes are created for the purpose of arranging elements to best accomplish a particular purpose. The purpose is usually being informed by a business objective and a creative idea. The wireframe depicts the page layout or arrangement of the website's content, including interface elements and navigational systems, and how they work together.[2]:131 The wireframe usually lacks typographic style, color, or graphics, since the main focus lies in functionality, behavior, and priority of content.[1]:167 In other words, it focuses on what a screen does, not what it looks like.[1]:168 Wireframes can be pencil drawings or sketches on a whiteboard, or they can be produced by means of a broad array of free or commercial software applications. Wireframes are generally created by business analysts, user experience designers, developers, visual designers, and by those with expertise in interaction design, information architecture and user research.
<span>D. Make changes to your code
Variables allow the ability to easily substitute numbers for other numbers.
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