Dr. Stevens wants to examine the relationship between body mass index (BMI) and depression. He selects as his research subjects a sample of American athletes who are currently training for the summer Olympic Games. Dr. Stevens finds no relationship between BMI and depression. Which of the following is one problem with his research design that could have kept him from finding a relationship between those variables?
There is a restriction-of-range problem.

Read this example of social change in the american society and identify the agent that caused this change. in less than five years almost twenty-five percent of americans had access to the internet a . education b. population c . war and revolution d. science and technology

Que actos del pueblo simbolizaron el inicio de la revolucion y la caida de la monarquia?

Consider the speakers in "the raven" and the speaker in "the song of wandering aengus." write two paragraphs to compare and contrast the voice in these two poems. how does the poet give the speaker in each poem a distinctive voice? what effect does this voice have in each poem? use examples from each poem to as evidence for your answer "the raven"once upon a midnight dreary, while i pondered, weak and weary,over many a quaint and curious volume of forgotten lore—while i nodded, nearly napping, suddenly there came a tapping,as of some one gently rapping, rapping at my chamber door.“‘tis some visitor,” i muttered, “tapping at my chamber door—only this and nothing more.”ah, distinctly i remember it was in the bleak december, and each separate dying ember wrought its ghost upon the floor. eagerly i wished the morrow; —vainly i had sought to borrowfrom my books surcease of sorrow—sorrow for the lost lenore—for the rare and radiant maiden whom the angels name lenore—nameless here for evermore.and the silken sad uncertain rustling of each purple curtainthrilled me—filled me with fantastic terrors never felt before; so that now, to still the beating of my heart, i stood repeating“‘tis some visitor entreating entrance at my chamber door—some late visitor entreating entrance at my chamber door; this it is and nothing more.”"the song of wandering aengus." i went out to the hazel wood,because a fire was in my head,and cut and peeled a hazel wand,and hooked a berry to a thread; and when white moths were on the wing,and moth-like stars were flickering out,i dropped the berry in a streamand caught a little silver trout.when i had laid it on the floori went to blow the fire aflame,but something rustled on the floor, and some one called me by my name: it had become a glimmering girlwith apple blossom in her hairwho called me by my name and ranand faded through the brightening air.plz hurry