1. The odometer of the family car shows 15,951 miles. The driver noticed that this number is palindromic: it reads the same backward and forward. "Curious," the driver said to himself. "It will be a long time before that happens again." But 2 hours later, the odometer showed a new palindromic numbrer. How fast was the car traveling in those 2 hours?
2. Samantha has 1 penny, 2 nickels, and 1 dime. How many different sums of money can she make, if she uses at least 1 coin.
3. Write 2014 with the first four prime numbers, with the aid of the operations addition, multiplication and exponentiation.
4. The five-digit number 3a,5a7 is a multiple of 9, and each 'a' represents the same digit. What digit does 'a' represent?
