Are these sentences correct and natural?
(1) She had a summer internship at google which was tough but worth it.
(2) Before finding a solid evidence, we cannot rule out the possibility that anyone in this class could be a murderer.
(3) In the capitalism society, winners are always those who have established connections towards celebrities, politicians and wealthy business men.
(4) You can earn more benefits at young age if you are well-connected.
(5) Being skilled at communication and public speaking can open the door to the happiness and confidence.

Question

Are these sentences correct and natural?
(1) She had a summer internship at google which was tough but worth it.
(2) Before finding a solid evidence, we cannot rule out the possibility that anyone in this class could be a murderer.
(3) In the capitalism society, winners are always those who have established  connections towards celebrities, politicians and wealthy business men.
(4) You can earn more benefits at young age if you are well-connected.
(5) Being skilled at communication and public speaking can open the door to the happiness and confidence.

Answer

1) is fine
2) a solid evidence.... evidence is uncountable so you need something like "any solid evidence"
3) capitalist society... to not towards.  Just out of interest that is also true nearly all societies, parents love their children and connections are connections
4) at A young age
5) can open the door to      happiness.  (no the)

It is easy to correct sentences in the other question area, this area is just for answers.