Giáo trình tiếng anh điện tử viễn thông - digital telephone exchanges p7

There is a 270 millisecond propagation delay, …………….. the signal has to travel thousands of kilometres. a. consequently a. as a result b. since b. for 3. The rockets were lost at sea and, ……………….., the launches were expensive. 4. The shuttle heralds a new era of space travel ……………… it can perform at least 100 separate missions. a. consequently b. as