【单选题】The amount of sunlight reaching Earth's surface appears to be growing. The phenomenon, which some dub 'global brightening', (1)_____ scientists with a puzzle. If the (2)_____ is real and global, how l...
【判断题】Euthanasia is the act or practice of killing or permitting the death of hopelessly sick or injured individuals (such as persons or domestic animals) in a relatively painless way for reasons of mercy. ...