help please thanks

1.) CD ROM has 5 files burn in it with 2.35 MB capacity. How much capacity has been used in Bytes?

2.) A doc file with 250KB, ppt file with 25MB and xls file with 20MB were allocated in a DVD with a 4.7Gb capacity per layer. How much capacity is still available for saving? (GB)

3.) Die hard DVDRip of 2.09GB capacity, The Net DVDRip of 1.89GB, 10 songs of 5.5MB were also burn and pdf files with 100MB is allocated in the Blue Ray Disc, How much is the remaining capacity in KB and the capacity has been utilized in MB?