If you are writing words, yes. But it looks better to say 5:30 rather than five-thirty.
You do not need to hyphenate.
No. It is three thirty, but in five minutes time it will be three thirty-five.
You do not hyphenate 30 minutes, as in "She took thirty minutes to finish her test."You do, however, hyphenate 30-minute as in, "She took the thirty-minute exam."The distinction is that in this latter case 'thirty-minute' is used as a compound adjective (describing the timed exam) whereas in the first example 'thirty' is an adjective describing 'minutes'.An easier way to remember it is that you only hyphenate when the adjectives are acting together for a single purpose (such as modifying a single word together).
Six times five is thirty
You don't.
Thirty five Thirty-five
The time 'two-thirty and thirty-five seconds' would be written: 2:30:35.
It is three and thirty-five hundredths
Seventeen and thirty-five hundredths is 17.35
Thirty-five hundredths.
thirty-five-hundredths = 0.35
Thirty-five thousandths