Mouth ulcers are also a possible symptom of a viral infection that mainly affects young children, called hand, foot and mouth disease. Speak to your GP or call NHS 111 if you're unsure. Read about the symptoms of hand, foot and mouth disease.
It was not until 1965 that a national upper limit of 70mph was introduced for all roads, including motorways. Since 1977 the speed limit for cars and motorcycles on dual carriageways has been 70mph, with a 60mph speed limit on single carriageways.
The increases have continued apace. Today, six states have 80 mph limits, and drivers in Texas can legally drive 85 mph on some roads. The new study looked at the effect of all speed limit increases from 1993 to 2013 in 41 states.