"an" is used before a vowel sound, and "a" is used before a consonant sound. the word sound is important because consonants can create vowel sounds, and vowels can create consonant sounds. therefore, the use of "an" or "a" is determined by the sound not the letter. look at these examples: a house an...
measurement aircraft equipment/marine device/magnetic measurement shimadzu offers flight control systems to help ensure safe flight operations and comfortable space for passengers. optical and laser devices optical and laser devices shimadzu offers high-precision optical devices such as diffraction...
and its transmission. some of his results are preserved in thomson's annals of philosophy for . he recognised that sound is propagated by waves or oscillations of the atmosphere, as light was then believed to be by undulations of the luminiferous ether . water, and solid bodies, such as glass, or metal...
borchgrevink the first expedition to overwinter on the antarctic mainland ( cape adare ), borchgrevink's expedition was the first to make use of dogs and sledges. it made the first ascent of the great ice barrier , [ ] and set a farthest south record at ° 's. it also calculated the location of the south magnetic...