Answer: Wendy did not use random assignment
Explanation: Wendy's failure to randomly assign participants or subject to his research will pose a threat to the internal validity of his study. The internal validity of a study simply refers to the structure of an experiment and it's trustworthiness in establishing causal relationship between the applied treatment used a study and the observed outcome. Wendy's decision to ignore random assignment and opt for a manual assignment of subject to each treatment will pose a threat to the structure of his study and hence the establishment of a causal relationship between the treatment t and outcome of the study.
Answer:
Sand Stones!
Explanation:
Sand Stones are the most common types of sedimentary rocks.
Answer:
Tarai, also spelled Terai, region of northern India and southern Nepal running parallel to the lower ranges of the Himalayas. A strip of undulating former marshland, it stretches from the Yamuna River in the west to the Brahmaputra River in the east.The Terai region is a haven for wildlife.