Solve the following problems:

Of the 200 candidates who were interviewed for a position at a call center, 100 had a two- wheeler, 70 had a credit card and 140 had a mobile phone, 40 of them had both, a two-wheeler and a credit card, 30 had both, a credit card and a mobile phone and 60 had both, a two- wheeler and mobile phone and 10 had all three. How many candidates had none of the three?

Jane covered a distance of 340 miles between city A and city B taking a total of 5 hours. If part of the distance was covered at 60 miles per hour speed and the rest at 80 miles per hour speed, how many hours did the travel at 60 miles per hour?