要素1

要素2

要素3

function sample1Func(){
  var h5 = document.getElementsByTagName("h5");
  h5[1].style.color = "red";
}
	

要素1

要素2

要素3

var sample2Btn = document.getElementById("sample2Btn");
var h4 = document.getElementsByTagName("h4");
sample2Btn.onclick = function(){
  h4[0].innerHTML = "element1";
  h4[1].innerHTML = "element2";
  h4[2].innerHTML = "element3";
}
	

function s3Func(){
  var s3Div = document.getElementById("s3Div");
  var s3p = s3Div.getElementsByTagName("p");
  var newP = document.createElement("p");
  newP.innerText = "newP";
  var s3Random = Math.floor(Math.random()*s3p.length);
  s3p[s3Random].append(newP);
}
	

function s4Func(){
  var h3 = document.getElementsByTagName("h3");
  for(var count=1; count<31; count++){
	h3[count+3].innerHTML = count;
  }
}