采用多道程序设计技术，能有效地提高系统的下列哪一个性能?
A、并发性A
并发运行是指在计算机系统中同时存在若干个运行着的程序，各进程均处于已开始运行与结束之间， 宏观上各进程并行运行， 正是多道程序设计技术的出现使得程序的并发执行成为可能。
Werefertothelimitedrangeofsoundsasthephonicmediumoflanguageandindividualsoundswithinthatrangeas______.
Bythemiddleofthe21stcentury,thevastmajorityoftheworld’spopulationwillbelivingincities_______inthecountry.
FiftycasesofGreenTeayousentuswerefoundtobebadlydamaged.Thiswasapparentlyattributableto____packing.()
OneofthedisadvantagesintheGrammar-TranslationMethodisthatthetextsaretakenfrom_____,thelanguageofwhichdoesn'toftenmeetthepracticalneedsofthelearners.
Canyouofferusmachinetools___thefollowingspecification?
