Results of a recent study reveal insights on perceptions and attitudes toward mobileshopping. The study results show that $26\%$ of consumers indicate that in$-$app recommendations would drive them to add more items to their cart and that $35\%$ would spend more time in the app. But shopper priorities change the moment they need$$ help; they expect to get it immediately and effortlessly. If forced to stop what$$ they're doing and leave the app to get$$ help, $1$ out of $4$ shoppers would likely not make a purchase with the brand at all. The research is based on an online survey with a sample of $1,500$ U$.$S$.$ adults who have made purchases via their mobile device. Complete parts$($a$)$ through$($d$)$ below.

b$.$ Describe the sample that was collected.