computer networks plz help me

in HFC the optical line terminator at the network side and ONT to conver signals Select one: a. to optical signals at the network side O b. to electrical signals at the network side O c. to end signal transmission File lingth is 32 million bits and Rs=4Mbs Rc=2Mbs what is the time Select one: O a. 32s O b. 8s O c. 16 s