6) The sales that were made through the online 3rd party are not available in the provided data. Thus far we have analyzed the relationship between introducing an online delivery channel and the in-store sales of a grocery store. The grocery store is thinking about making the online option available at all stores. Discuss why the data limitation mentioned (a lack of online delivery option sales data) limits what we can conclude about the overall effect of a grocery store introducing an online delivery option. [1 point]