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Planning a visiting to the UK ? Here we help with ways to cut your costs. AVOID BIG EVENTS Big sporting events , concerts and exhibitions can increase the cost of accommodation and make it harder to find a room . A standard double room at the Thistle Brighton on the final Friday of the Brighton Comedy Festival (19 Oct.) cost $220 at Booking .com.  A week later , the same room just cost $170 . If you can be flexible and want to know dates to avoid --- or you’re looking for a big event to pass your time --- check out sites such as Whatsonwhen.com , which allow you to search for events已知圆的圆心是直线与轴的交点，且圆与直线 相切，则圆的方程是(    )A．B．C．D．