申論 5何謂電子海圖（Electronic Navigation Chart；ENC）？另外，電子海圖顯示及資訊系統（Electronic Chart Display and Information System ; ECDIS）的發展趨勢及特點為何？試分別說明之。（24 分）附件1TABLE 18Distance of an Object by Two BearingsDifference between the Difference between the course and first bearingcourse and second bearing 26° 28° 30° 32°°