The first eastbound central line train has arrived at Stratford station, following an earlier part-suspension of the service today caused by a fire alert.
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The poll comes ahead of a debate in the House of Commons on Friday on a new Bill which would introduce such a system in England.
Jobs with decent pay and flexibility are "few and far between" for single parents who are the main earner and carer, said the report.
Coal's share of the power mix had fallen to 7%, while wind climbed to new highs to provide 15% of the country's electricity.