What is an observational study? How is it different from a controlled experiment?

Observational study is when you observe your subject and take more notes rather that writing down quantitative data. Meanwhile, a controlled experiment is more quantitative.

Explanation:

are there any answer choices

the correct answer is: d. the saltine and pretzel are made of flour, yeast, and baking soda, and salt. the pecan contains no flour but it does contain fats. the pecan is a nut that can be consumed as a healthy snack. first of all, pecans are a source of fat (monounsaturated fat), but they provide less fat than some other nuts. pecans are a rich source of dietary fiber, manganese magnesium, phosphorus, thiamin, vitamin e…