few_shots: Example:
Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Mathematical concept/skill options: 
A. Prove and apply trigonometric identities.
B. Model periodic phenomena with trigonometric functions.
C. Interpret functions that arise in applications in terms of the context.
D. Build a function that models a relationship between two quantities.
E. Define, evaluate, and compare functions.
F. Use functions to model relationships between quantities.
G. Understand the concept of a function and use function notation.
H. Analyze functions using different representations.
I. Extend the domain of trigonometric functions using the unit circle.
J. Interpret expressions for functions in terms of the situation they model.
K. Build new functions from existing functions.
L. Construct and compare linear and exponential models and solve problems.


Your response, in json format:
{
  "explanation": "This problem applies trigonometric identities, including the angle addition formula for cosine.",
  "answer": "A"
}

Now, assign the following problem or activity to one or more relevant mathematical concepts/skills it teaches.
shot_info: fl_problem_001894

HS
options: Use place value understanding and properties of operations to add and subtract.

Work with numbers 11–19 to gain foundations for place value.

Generalize place value understanding for multi-digit whole numbers.
Grade 4 expectations in this domain are limited to whole numbers less than or equal to 1,000,000.

Understand place value.

Perform operations with multi-digit whole numbers and with decimals to hundredths.

Understand the place value system.

Use place value understanding and properties of operations to perform multi-digit arithmetic.
Grade 4 expectations in this domain are limited to whole numbers less than or equal to 1,000,000.

Use place value understanding and properties of operations to perform multi-digit arithmetic. (A range of algorithms may be used.)

Extend the counting sequence.
problem_activity: Narrative
The purpose of this activity is for students to have another chance to practice skip-counting by 2, 5, and 10 and addition and subtraction within 1,000.
Required Materials
Materials to Gather
Materials from previous centers
Required Preparation
Gather materials from:
Write Numbers, Stage 4
Target Numbers, Stages 6 and 7
Five in a Row, Stages 7 and 8
How Close, Stage 4
Launch
“Now you will choose from centers we have already learned.”
Display the center choices in the student book.
“Think about what you would like to do first.”
30 seconds: quiet think time
Activity
Invite students to work at the center of their choice.
15
–
20 minutes: center work time
“Choose what you would like to do next.”
15
–
20 minutes: center work time
If time allows, have students choose a third center to work on.
Student Facing
Choose a center.
Write Numbers
[IMG]
Target Numbers
[IMG]
Five in a Row
[IMG]
How Close
[IMG]
Activity Synthesis
Invite 2-3 students to share their favorite method for adding and subtracting within 1,000.


correct_option_index: 0

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