There is a 7-digit telephone number with all different digits. If the digit at extreme right and extreme left are 5 and 6 respectively, find how many such telephone number are possible ?

There is a 7-digit telephone number with all different digits. If the

1.	There is a 7-digit telephone number with all different digits. If the digit at extreme right and extreme left are 5 and 6 respectively, find how many such telephone number are possible ?
A.	120
B.	100000
C.	6720
D.	30240
E.	None of the above
Answer» D. 30240