Distinct Subsequences

The first line is an interger Q（ Q = 50 ）, indicating the number of test cases.
Then in each case:
The first line is the string S, and the second line is the string T. ( 0 < |S|, |T| ≤ 1e4 )
The data guarantee every character of T is randomly generated.

Q lines and each line contains an interger P, representing the number of different subsequences of S which is equal to T.
Since P maybe very large, you should output it after module 1000000007(1e9+7).