As a rapidly-moving train passes with a sustained whistle, the pitch changes as the train whizzes by. Why does this happen?
a..................................................................This is an illusion in the mind of the listener.
b.Sound waves are compressed in the direction of the train's movement and lengthened behind it.
c.Doppler thinks it's because of interference from the accompanying sound created by the wheels on
d......................................Because the train is moving faster than sound waves can travel.
b
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In which step of the Vocabulary Acquisition model might the teacher gather information about what students already know, to inform subsequent learning activities?
a. Exploring patterns of meanings b. Evaluating and post-testing c. Pretest of knowledge d. Elaboration on hypothesizing meanings
In the ______ characteristic of action research, the study uses subjective reflection about self and how the self impacts practice.
A. reflection B. relationship C. decision-making D. impact
Travis has been training his puppy, Belle, to sit by the back door and bark when she wants to go outside and "do her business." First, Travis let her out, provided her with tons of praise, and gave her a treat (all presumed reinforcers) if she sat by the back door and then when outside and urinated. Then, Travis withheld reinforcement for this behavior and provided the reinforcers only if she sat
by the door and made a small noise (i.e., a whine). Now that she does that well, Travis is withholding reinforcement for that behavior and only providing the reinforcers if she sits by the door and makes a bark. What has Travis been doing? a. Shaping sitting by the door and barking when Belle has to urinate. b. Using differential reinforcement to teach Belle to sit by the door and bark when she has to urinate. c. Using backward chaining to teach Belle to sit by the door and bark when she has to urinate. d. A & B e. B & C
People working with collaborative programs must have ways to determine how well their goals are being met. This process is known as
A) communication. B) assessment. C) planning. D) collaboration.