题目

Events for Mother’s Day High tea by the Thames The London Eye is offering a selection of Mother’s Day packages this year including a special afternoon tea for £55 per person. Your mum will be served sandwiches and Battenberg cake while admiring wonderful views of the London city. There’ll also be a chocolate tasting experience for £47 per person that includes a glass of Prosecco and a Hotel Chocolat goodie bag. Cookery class in Dorest Famous chef Lesley Waters is holding a half-day Mother’s Day cookery class on Saturday 29 March at her cookery school in Dorest for just £20 pe（2010•荆门）已知a=2+，b=2-，试求的值．