a researcher is studying the effects of playing chess on memory improvement. he identifies 50 people who play chess and 50 people who do not. each of the 100 people is given a questionnaire designed to determine memory level. none of the 100 people who participated in the study knew they were part of a study. which statement is true.

Observational study

Step-by-step explanation:

Just took the test

i dont know sorry

step-by-step explanation:

his first public project he is asked to create a small scale drawing. the garden is a right triangle with base 25m and height 30m. are you trying to solve for the last side/hypotenuse? the irrational form of the answer would be 5\sqrt{61}