Calculating the area of compound shapes - BBC Bitesize

・・・ In the Bay, your area code is your Identity 💯 415 was the first. Back in 1947, it covered SF, Oakland, San Jose, and most of Northern California. But as the Bay grew, so did the codes: 408 took San Jose in ‘59. 707 split off the same year—Vallejo, Napa, and the North Bay. 510 dropped in ‘91—Oakland, Berkeley, Hayward. 650 came in ‘97—Daly City, Palo Alto, the Peninsula. 925 showed up in ‘98—Concord, Antioch, Walnut Creek. Your area code was your identity. It wasn’t just where you lived—it w