OSAT Elementary Education
1. Homonyms such as bare and bear are similar in sound yet have different meanings. What would a teacher suggest a student do to avoid misusing these words?
- Memorize the definitions of the difficult words.
- Check a dictionary or thesaurus to verify a word's usage.
- Avoid encountering difficult words.
- Ignore being precise in the definition.
2. A magician has a hat that holds two rabbits. One rabbit is black and the other is white. In his last 16 performances he has randomly pulled the black rabbit from the hat 16 times. The probability that he will pull the white rabbit from the hat in his next performance is:
3. "Language load" refers to:
- The basic vocabulary words a first grader has committed to memory
- The number of unrecognizable words an English Language Learner encounters when reading a passage or listening to a teacher
- The damage that carrying a pile of heavy books could cause to a child's physique
- The number of different languages a person has mastered.
4. The necessary and sufficient condition for a prime number is:
- Divisible only by itself and 1
- Divisible only by itself
- Is not a product of two numbers
- Is the product of prime numbers
5. Which of the following represents a chemical change?
- Sublimation of water
- A spoiling apple
- Dissolution of salt in water
- Pulverized rock
Answers & Explanations
1. B: Checking a dictionary or thesaurus will ensure correct usage of a word. A is incorrect because memorization may not cover all the potential difficult words. C is incorrect because it is not possible to avoid encountering difficult words. D is incorrect because a precise understanding is necessary for comprehension.
2. A: The events, if truly random, are independent of each other. There is therefore an equal probability of pulling the black rabbit or the white rabbit from the hat each time. The probability is therefore 0.50.
3. B: The number of unrecognizable words an English Language Learner encounters when reading a passage or listening to a teacher. Language load is one of the barriers English Language Learners face. To lighten this load, a teacher can rephrase, eliminate unnecessary words, divide complex sentences into smaller units, and teach essential vocabulary before the student begins the lesson.
4. A: A prime number is by definition any number that can be divided integrally only by itself and 1. It therefore has no factors and so is not the product of any other numbers, prime or otherwise.
5. B: A spoiling apple. A spoiling apple is an example of a chemical change. During a chemical change, one substance is changed into another. Oxidation, a chemical change, occurs when an apple spoils. Answer A, Sublimation of water, refers to the conversion between the solid and the gaseous phases of matter, with no intermediate liquid stage. This is a phase change, not a chemical reaction. Answer C, Dissolution of salt in water, refers to a physical change, since the salt and water can be separated again by evaporating the water, which is a physical change. Answer D, Pulverized rock, is an example of a physical change where the form has changed but not the substance itself.
Last Updated: 03/01/2017