How I can Add Jest as a dev Dependency as first task - jestjs

Question

Task 1: Add Jest as a devDependency
Open terminal. Make sure that it's pointing to jest-testing directory.
Install the jest npm package using the npm install command and the --save-dev flag.
Verify that the installation was completed successfully by opening the package.json file and confirming that the "devDependencies" entry lists jest similar to the following:
"devDependencies": {
"jest": "^28.0.0"
}
Task 2: Update the test entry
In the package.json file, locate the "scripts" entry, and inside of it, update the test entry to jest.
Task 3: Code the timesTwo function
Open the timesTwo.js file and add a function named timesTwo. The function should take number as input and return the value 2 multiplied by the number.
Export the timesTwo function as a module.
Task 4: Write the first test
Code a test call with the following arguments:
The description that reads: "returns the number times 2".
The second argument should expect the call to the timesTwo function, when passed the number 10, to be 20.
Task 5: Run the first test
With the terminal pointed at the jest-testing directory, run the test script using npm.

Answer 1

Task 1: Add Jest as a devDependency
use comands
cd jest-testing
node --version
npm --version
npm init -y
npm install --save-dev jest
Task 2: Update the test entry
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Task 3: Code the timesTwo function
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Task 4: Write the first test
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Task 5: Run the first test
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