6．某仓库内要存放一台自重40吨的设备，该设备底架为两条2米<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/web/icve/mooc/1a72eeabb39ae865ec8c826cb71d3962.gif?x-oss-process=image/sharpen,200,http://www.icve.com.cn/common/js/ueditor/themes/default/images/word.gif"/>0.2米的钢架，该仓库库场单位技术定额为3吨/平方米，如采用2米<img src="http://jgxm-question.oss-cn-beijing.aliyuncs.com/web/icve/mooc/1a72eeabb39ae865ec8c826cb71d3962.gif?x-oss-process=image/sharpen,200,http://www.icve.com.cn/common/js/ueditor/themes/default/images/word.gif"/>1米自重为1吨的钢板垫垛，需 [填空(1)] 块。