设<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/ad19d836a70d443990e68b89b7a2d655.png?x-oss-process=image/sharpen,200"/>是下半球面<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/1af09e4a22ad43cc94d6a3822e2ca479.png?x-oss-process=image/sharpen,200"/>的下侧，<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/02981380d36040d1b14ed9456435fbe6.png?x-oss-process=image/sharpen,200"/>是<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/ad19d836a70d443990e68b89b7a2d655.png?x-oss-process=image/sharpen,200"/>与<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/7ac13c51c4f74fd8b076402c8e1a20a1.png?x-oss-process=image/sharpen,200"/>所围成的空间闭区域，则<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/psst/files/2262e5f6ce994a978fd52130fad67e33.png?x-oss-process=image/sharpen,200"/>（）.