answer:srcObject是一个JavaScript属性，用于指定媒体流的来源。它通常用于在WebRTC应用中将本地视频或音频流绑定到一个HTML video或audio元素上，从而实现视频聊天、会议、直播等功能。 具体来说，开发者可以通过getUserMedia()方法获取摄像头或麦克风的视频或音频流，并通过srcObject属性将这些流绑定到HTML元素上。例如： ```javascript // 获取本地摄像头的视频流 navigator.mediaDevices.getUserMedia({ video: true }) .then(function(stream) { // 获取video元素 var video = document.querySelector('video'); // 将视频流绑定到video元素上 video.srcObject = stream; }) .catch(function(err) { console.log('getUserMedia error:', err); }); ``` 这里将获取到的本地摄像头视频流绑定到了一个video元素上，使其显示了摄像头捕获的实时视频内容。

answer:無異曲線（isochrone curve）是一個在物理和數學中出現的概念，指的是在給定時間內各點到達某個位置的時間相同的曲線。這些曲線主要應用於地球科學、交通規劃、地理信息系統等領域，用於描述從某一點出發在相同時間內可以到達的範圍。 無異曲線具有以下特性： 1. 質點沿著無異曲線運動時，速度與時間無關。這意味著質點在無異曲線上任意兩點之間的運動需要相同的時間，無論其運動速度如何變化。 2. 無異曲線在地圖上呈閉合環形，表示出發點在給定時間內可以到達的範圍。 3. 無異曲線可用於分析交通網絡、擴散過程等問題。例如，在城市交通規劃中，根據無異曲線可以確定在某段時間內公共交通可以覆蓋的範圍，以及評估不同交通方式之間的效率。 4. 無異曲線具有一定的平滑性，在給定條件下，不會出現突變等異常情況。 在實際應用中，無異曲線可以根據速度、距離、時間等參數生成相應的曲線。透過無異曲線的分析，可以更好地理解不同地區之間的相互連接性和交通效率，從而為許多科學研究和專業領域提供有價值的信息。

answer:While the list of substances you provided includes many essential nutrients (amino acids, fatty acids, vitamins, minerals, and more), it still does not encompass the full range of nutrients that a human needs to survive and maintain proper body function. A few key components missing from the list include: 1. Dietary fiber: Crucial for proper digestion, maintaining bowel health, and controlling blood sugar levels. 2. Antioxidants and other phytonutrients: These compounds occur naturally in various plant foods, and help protect our cells from damage and support overall health. 3. Complete proteins: While your list includes several essential amino acids, it is not clear if they would be present in the right proportions to provide a balanced source of protein for maintaining muscle mass, immunity, and other vital bodily functions. 4. Other potential trace elements, bioactive compounds, and components which may contribute to a balanced diet. Also, it's important to remember that many of these nutrients interact with each other and with other food components to support optimal health, meaning that consuming them in isolation may not yield the same health benefits as eating a varied and balanced diet. While consuming the substances on your list may help support some aspects of health, a person would likely face deficiencies or imbalances in other nutrients over time that could lead to health problems or physical dysfunction. It's always best to strive for a balanced, whole-foods based diet for optimal human health and longevity.

answer:Le questionnaire de santé ou médical rempli et signé par l'emprunteur.