Cloyd's Supermarket, a popular retail store, sells a variety of products. In order to assess if it needs to make improvements to its service, the marketing research team sends out questionnaires to Cloyd's regular customers. The questionnaire has questions with blank spaces below. The customers have to write what they like best about shopping at Cloyd's and what new products or services they expect from Cloyd's. The questions included in the questionnaire are examples of _____.