Edit in JSFiddle

const data = {
	"dcids": [
		"wikidataId/Q1960",
    "wikidataId/Q3866"
	]
}
const request = new XMLHttpRequest();
request.open("POST", "https://api.datacommons.org/place/stat-vars", false /* async */ );
request.send(JSON.stringify(data));

if (request.status == 200) {
  let result = JSON.parse(request.responseText)["places"];
  console.log(result);
  
  for (const key of Object.keys(result)) {
  	document.getElementById(key).innerText = result[key]["statVars"];
  }
  
} else {
  console.log("There was an error fetching data.");
}

Statistical variables available for the city of Dodoma, Tanzania:
<div id="wikidataId/Q3866">
</div>

Statistical variables available for the city of Dar es Salaam, Tanzania:
<div id = "wikidataId/Q1960">

</div>