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: Geometric measurement: understand concepts of angle and measure angles.

Geometric measurement: recognize perimeter as an attribute of plane figures and distinguish between linear and area measures.

Solve problems involving measurement and estimation of intervals of time, liquid volumes, and masses of objects.

Describe and compare measurable attributes.

Geometric measurement: understand concepts of area and relate area to multiplication and to addition.

Solve problems involving measurement and conversion of measurements from a larger unit to a smaller unit.

Relate addition and subtraction to length.

Represent and interpret data.

Tell and write time.

Convert like measurement units within a given measurement system.

Geometric measurement: understand concepts of volume and relate volume to multiplication and to addition.

Measure lengths indirectly and by iterating length units.

Classify objects and count the number of objects in each category.

Work with time and money.

Measure and estimate lengths in standard units.
problem_activity: Narrative
The purpose of this activity is for students to learn stage 2 of the Estimate and Measure center. Students estimate and measure the length of objects. This stage includes centimeters, inches, and feet. Students should only measure in centimeters at this point in the unit. In this activity, students also find the difference between their estimate and their measurement for extra practice.
Required Materials
Materials to Gather
Metersticks
Objects of various lengths
Rulers (centimeters)
Materials to Copy
Estimate and Measure Stage 2 Recording Sheet
Required Preparation
Gather or identify objects of various lengths (pencils, markers, books, glue, scissors, shoe, tape dispenser, side of desk, length of bulletin board).
Launch
Groups of 2
Give students access to centimeter rulers and meter sticks.
Give each student a recording sheet.
“We are going to learn a new center called Estimate and Measure. Today we are going to estimate and measure the length of different objects.”
“First you and your partner will decide on an object in the room to measure. Then you will decide what tool you will use to measure the object.”
Choose an object to measure and hold it up for students to see.
“What tool would you use to measure this object?”
“Before measuring the object, you and your partner will both estimate the length of the object using the unit you chose. Your estimates do not have to be the same. Record your estimate.”
Demonstrate estimating the length of your object and recording it on the recording sheet.
“Now work with your partner to measure the object and record the actual measurement.”
Demonstrate measuring the object, thinking aloud as you line up the endpoints and use the number on the tool to determine the length.
Record the actual measurement on the recording sheet.
“If you have time: Once you have estimated and measured the object, find the difference between your estimate and the actual length.”
Demonstrate finding the difference.
“Put your object back and choose another object to measure.”
Activity
10 minutes: partner work time
Activity Synthesis
Display a row of the recording sheet with this information:
Object: notebook
Estimate: 20 cm
Actual Measurement: 31 cm
“How can we find the difference?” (We can add on to 20 until we get to 31. We can subtract 20 from 31.)


correct_option_index: 14