What is the result?() ["420 is the output.","An exception is thrown at runtime.","All constructors must be declared public.","Constructors CANNOT use the private modifier.","Constructors CANNOT use the protected modifier."]
简述原核微生物基因重组的主要方式及其特点?
针对直流电机,我国标准的电气控制柜设计的快速启动原则中启动电阻为() ["1-2段","2-3段","3-4段","4-5段"]
下列宿根花卉中()的别称也叫忘忧草。 ["菊花","萱草","麦冬","君子兰"]
“儿童自我状态”的个性特征是() ["服从","任性","冲动","客观","优越感"]
闪光继电器一般有(),()和()三种类型,现以()用得最多。