Answer : 2. "360"
Explanation :

Answer: B) 360 Explanation: There are 7 digits 1, 2, 0, 2, 4, 2, 4 in which 2 occurs 3 times, 4 occurs 2 times.    Number of 7 digit numbers = 7!3!×2! = 420   But out of these 420 numbers, there are some numbers which begin with '0' and they are not 7-digit numbers. The number of such numbers beginning with '0'.   =6!3!×2! = 60   Hence the required number of 7 digits numbers = 420 - 60 = 360