安全电压的三个级别分别是()、()、()
参考答案:12V;24V;36V
Jane has been so ______ in getting used to everything that she hasn’t had time for social activities.
A.occupied
B.confused
C.devoted
D.worried
智能发电主要涉及()等3大技术领域。
A.常规能源
B.清洁能源
C.大容量储能应用
D.可再生能源