diff --git a/js/least-squares-regression-main.js b/js/least-squares-regression-main.ts
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diff --git a/js/least-squares-regression/LeastSquaresRegressionConstants.js b/js/least-squares-regression/LeastSquaresRegressionConstants.ts
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rename from js/least-squares-regression/LeastSquaresRegressionConstants.js
rename to js/least-squares-regression/LeastSquaresRegressionConstants.ts
diff --git a/js/least-squares-regression/LeastSquaresRegressionScreen.js b/js/least-squares-regression/LeastSquaresRegressionScreen.ts
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rename from js/least-squares-regression/LeastSquaresRegressionScreen.js
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diff --git a/js/least-squares-regression/model/DataPoint.js b/js/least-squares-regression/model/DataPoint.ts
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diff --git a/js/least-squares-regression/model/DataSet.js b/js/least-squares-regression/model/DataSet.ts
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diff --git a/js/least-squares-regression/model/Graph.js b/js/least-squares-regression/model/Graph.ts
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diff --git a/js/least-squares-regression/model/LeastSquaresRegressionModel.js b/js/least-squares-regression/model/LeastSquaresRegressionModel.ts
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rename from js/least-squares-regression/model/LeastSquaresRegressionModel.js
rename to js/least-squares-regression/model/LeastSquaresRegressionModel.ts
diff --git a/js/least-squares-regression/model/Residual.js b/js/least-squares-regression/model/Residual.ts
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diff --git a/js/least-squares-regression/view/BestFitLineControlPanel.js b/js/least-squares-regression/view/BestFitLineControlPanel.ts
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rename from js/least-squares-regression/view/BestFitLineControlPanel.js
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diff --git a/js/least-squares-regression/view/DataPointCreatorNode.js b/js/least-squares-regression/view/DataPointCreatorNode.ts
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diff --git a/js/least-squares-regression/view/DataPointNode.js b/js/least-squares-regression/view/DataPointNode.ts
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rename from js/least-squares-regression/view/DataPointNode.js
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diff --git a/js/least-squares-regression/view/DataSetComboBox.js b/js/least-squares-regression/view/DataSetComboBox.ts
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diff --git a/js/least-squares-regression/view/DynamicDataPointNode.js b/js/least-squares-regression/view/DynamicDataPointNode.ts
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diff --git a/js/least-squares-regression/view/EquationNode.js b/js/least-squares-regression/view/EquationNode.ts
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diff --git a/js/least-squares-regression/view/GraphAxesNode.js b/js/least-squares-regression/view/GraphAxesNode.ts
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diff --git a/js/least-squares-regression/view/GraphNode.js b/js/least-squares-regression/view/GraphNode.ts
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diff --git a/js/least-squares-regression/view/LeastSquaresRegressionScreenView.js b/js/least-squares-regression/view/LeastSquaresRegressionScreenView.ts
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rename from js/least-squares-regression/view/LeastSquaresRegressionScreenView.js
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diff --git a/js/least-squares-regression/view/MyLineControlPanel.js b/js/least-squares-regression/view/MyLineControlPanel.ts
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diff --git a/js/least-squares-regression/view/PearsonCorrelationCoefficientNode.js b/js/least-squares-regression/view/PearsonCorrelationCoefficientNode.ts
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diff --git a/js/least-squares-regression/view/ResidualLineAndSquareNode.js b/js/least-squares-regression/view/ResidualLineAndSquareNode.ts
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diff --git a/js/least-squares-regression/view/SourceAndReferenceNode.js b/js/least-squares-regression/view/SourceAndReferenceNode.ts
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diff --git a/js/least-squares-regression/view/StaticDataPointNode.js b/js/least-squares-regression/view/StaticDataPointNode.ts
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diff --git a/js/least-squares-regression/view/SumOfSquaredResidualsChart.js b/js/least-squares-regression/view/SumOfSquaredResidualsChart.ts
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diff --git a/js/leastSquaresRegression.js b/js/leastSquaresRegression.ts
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rename from js/leastSquaresRegression.js
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