[shahid3]

I'm trying to figure out the IUPAC name for the alkanes ,but I can't figure it out. I started by finding the longest carbon chain, and than numbered the carbons in the main chain so that the substituents have the lowest possible numbers. Than I substituted  using "di" ,"tri" ,and I tried others but I don't know what I am doing wrong. I'm usually good in making alkanes ,but I can't seem to figure out these 3.

[Dan]

Please post your attempts, then we can see where you're going wrong.