Incremental Backup

Hello Experts,

I need to know what happens when we take incremental backup if it is on tape and disk.

Sceneroi

Suppose we take

monday full backup on tape,  

tuesday differential incremental on disk

and wednessday differential incremental backup on tape again.

1:- Which type of backup would be done on tuesday on DISk. Would it be full or defferential incremetal as previously it was on tape?

2:- what will happen on wedessday? Does it take differentail incremental on wednessday from tuesday or from Monday full backup as there was a disk involved in  that?

3:- Or everything would be same full then differential incremental and again on wednessday incremental differntial.

Thanks,