minor typo, grammar fix for handbook/marketing/blog

Please provide a brief explanation for this change:

I found a minor typo and some incorrect grammar on this page. I changed it, because otherwise those sentences are confusing and/or jarring for the reader. Here's the fix for it!

Please indicate the types of revisions being suggested for the Product Handbook (please check all that apply):

• Small improvement (typos, clarifications, etc.)
• Adding a new section
• Modifying existing section
• Documenting a new process
• Adding a new page or directory
• Other

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• Provided a brief explanation for this change (Say why, not just what)
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• Indicated the types of changes included in this MR
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