Merge pull request #683 from GSA/bug/680-add-word-missing-from-lesson…

…4-purchase-pc

Update lesson04.mdx

training-front-end/src/content/training_purchase/lesson04.mdx

@@ -74,7 +74,7 @@ Refer to the [GPC](https://sftool.gov/greenprocurement) for the current list of
 
 ## What are biobased products?
 
-A Biobased product, also known as [BioPreferred® product](http://www.biopreferred.gov/BioPreferred/), is a commercial or industrial product (other than food or feed) that is composed, in whole or in significant part, of biological products, including renewable domestic agricultural materials (including plant, animal, and aquatic materials), forestry materials, intermediate materials, or feedstocks. Biobased products exclude motor vehicle fuels, heating oil, or electricity produced from biomass.
+A Biobased product, also known as a [BioPreferred® product](http://www.biopreferred.gov/BioPreferred/), is a commercial or industrial product (other than food or feed) that is composed, in whole or in significant part, of biological products, including renewable domestic agricultural materials (including plant, animal, and aquatic materials), forestry materials, intermediate materials, or feedstocks. Biobased products exclude motor vehicle fuels, heating oil, or electricity produced from biomass.
 
 In addition to strengthening the economy and supporting rural America, biobased products:
 - Help address climate change by offering renewable alternatives to petroleum-based products.