The term is hyphenated as "long-lasting" (persistent, perennial, long-lived).
Yes it should be hyphenated.
Yes, because you're using the phrase as an adjective (example: "This long-lasting lipstick is great."). Definitely use a hyphen.
Long-lasting
It should be hyphenated when it's used as an adjective.
I think Remy hair is the longest lasting hair!
Plastic is a non-biodegradable substance. Yes, it is long lasting.
Some examples of hyphenated words that start with "l" are: long-term, low-key, light-hearted, and life-threatening.
Same makers of viagra.
Long Lasting - 2011 was released on: USA: 2011
long-legged
The cream was meant to be long-lasting so she put it away for future use.