3- I can’t tell for certain, but it looks like a seedling in the Brassica oleracea (wild cabbage family)? In the cultivated types include cabbage, gailan, Kohlrabi, etc… But I’m only speculating, perhaps you could give us an update with flower’s photo when it booms if you still don’t know by then. link below is for cabbage seedlings. Best wishes! https://www.google.com/search?q=cabbage+seedling&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjX_vDlouXSAhXJ7CYKHcieCucQ7AkIKA&biw=1879&bih=909

2- Maybe Cindrella Weed/nodeweed (Synedrella nodiflora)? Link below for more information. http://keys.trin.org.au/key-server/data/0e0f0504-0103-430d-8004-060d07080d04/media/Html/taxon/Synedrella_nodiflora.htm

1- Maybe climbing spinach/Malabar spinach (Basella alba), check the flowers to confirm its ID. Link below with more information. Best wishes! https://en.wikipedia.org/wiki/Basella_alba