Fixed Typo

[TangentSquared]

Fixed Typo. Changed no to now in quiz.

Lesson authoring peer review checklist:

• [x] Includes authorship line: Text adaptation by [Name]
• [x] The lesson has an informative/compelling description, fit for a preview on the home page.
• [x] The lesson has no grammar/spelling errors
• [x] The lesson has no mathematical errors
• [x] The table of contents effectively conveys the overall structure of the lesson
• [x] The lesson uses no # Top Level headings
• [x] The lesson includes well-chosen comprehension questions
• [x] The lesson incorporates the core visuals from the video
• [x] The visuals are clear and helpful for understanding
• [x] The components are used in the places and ways they are intended (see the readme)

Website change review checklist:

• [x] I have requested a review from the appropriate persons
• [x] I have checked that my changes work in the preview
• [x] I have checked that the rest of the site is still functioning in the preview
• [x] I have checked that my content/code is consistent with existing content/code
• [x] I have used components in the places and ways they are intended (see the readme)
• [x] I have formatted all of my code with Prettier

This pull request:

-changes public/content/lessons/2019/windmills/index.mdx -fixed typo 'no' to 'now' in quiz

[3b1b]

Thanks!