Answer:
Why are there no living cats on Mars?
A man shaves several times a day, yet he still has a beard. Who is this man?
If you lose one of me, you are upset, bewildered, and perplexed. If you lose two of me, you are blissfully unaware. What am I?
Everyone in the world needs me. They generously give me but never take me. What am I?
What is easy to spot but hard to find?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.