Changing carbon dioxide emissions
How much have carbon dioxide emissions increased worldwide over the years?
Carbon dioxide emissions have almost tripled worldwide since 1965, according to the 2012 BP Statistical Review of World Energy, which has been compiling statistics about global energy since 1951.
Interestingly, U.S. carbon dioxide emissions have been on a downward trend since peaking in 2007. Emissions are now at 1992 levels, according to the U.S. Department of Energy.
But China's emissions have been rising steadily since 1999, and passed U.S. emissions in 2006, according to the Department of Energy.
Toll-free area codes (more to come)
What telephone prefixes are toll-free?
Toll-free phone number prefixes, or area codes, are 800 (since 1966), 888 (since 1996), 877 (since 1998), 866 (since 2000), 855 (since 2010) and 844 (since December 2013). These area codes are being reserved for future expansion: 833, 822, 880, 882, 883, 884, 885, 886, 887 and 889.
Regulation of these standards is in the hands of the North American Numbering Plan, which, according to its website, "is an integrated telephone numbering plan serving 20 North American countries that share its resources. These countries include the United States and its territories, Canada, Bermuda, Anguilla, Antigua and Barbuda, the Bahamas, Barbados, the British Virgin Islands, the Cayman Islands, Dominica, the Dominican Republic, Grenada, Jamaica, Montserrat, St. Maarten, St. Kitts and Nevis, St. Lucia, St. Vincent and the Grenadines, Trinidad and Tobago, and Turks and Caicos.
"AT&T developed the North American Numbering Plan in 1947 to simplify and facilitate direct dialing of long distance calls. Implementation of the plan began in 1951," according to the website.
Please, stop calling
Would you please list the conditions of the no-call list?
Charities, political organizations, surveyors, debt collectors and "companies with which you have an existing business relationship" are not covered by the National Do Not Call Registry, according to its website, donotcall.gov. "However, if a third-party telemarketer is calling on behalf of a charity, a consumer may ask not to receive any more calls from, or on behalf of, that specific charity." The registry is managed by the Federal Trade Commission.
What states have a "two-party consent" law for recording conversations or phone calls?
Florida, California, Illinois, Maryland, Massachusetts, Montana, New Hampshire, Pennsylvania and Washington, according to the Digital Media Law Project at Harvard University.
Compiled from Times and wire reports. To submit a question, email firstname.lastname@example.org.
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