How many 6-digit telephone numbers  can be constructed with digits 0,1,2,3,4,5,6,7,8,9 if each number starts with 35 and no digit appears more than once?

Number of 6 -digit telephone numbers, whichcan be constructed with digits 0,1,2,3,4,5,6,7,8,9, if each number starts with 35 and nodigit appears more than once is

How many 5-digits telephone numbers can be formed with the digits 0,1,2,….,8,9 if each numbers starts with 35 and no digit appears more than once?

How many 5-digit telephone numbers can be formed with the digits 0, 1, 2, 3, ….., 8, 9 if each number starts with 67 and no digit appears more than once ?

How many 8- digit telephone numbers can be constructed using the digits 0 to 9 if each number starts with 270 and no digit appears more than once?

How many 5 digit telephone numbers can be constructed using the digits 0 to 9, if each number starts with 67 and no digit appears more than once ?