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<html lang="pt-br">
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<meta charset="UTF-8">
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<title>Document</title>
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<canvas width="600" height="400"></canvas>
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var tela = document.querySelector('canvas');
var pincel = tela.getContext('2d');
pincel.fillStyle = 'lightgray';
pincel.fillRect(0, 0, 600, 400);
function desenhaCirculo(x, y, raio, cor) {
pincel.fillStyle = cor;
pincel.beginPath();
pincel.arc(x, y, raio, 0, 2*3.14);
pincel.fill();
}
desenhaCirculo(300,200,50,"red");
desenhaCirculo(300,100,50,"yellow");
desenhaCirculo(200,200,50,"orange");
desenhaCirculo(300,300,50,"blue");
desenhaCirculo(400,200,50,"black");
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