Does every size have 4 hooks in back?

34B-40B; 34C-36C = 3 Rows of Hooks38C-42C; 34D-40D; 36DD-40DD = 4 Rows of Hooks42D-42D; 42DD-42DD = 5 Rows of Hooks

The straps in the picture of the white bali bra 3036 do not look like they are comfy stretchable elastic like my old ones. Are they?

No, they are not. The band and the straps are shorter. The band has more elastic than the old ones. The straps have less and although they are adjustable they are so much shorter there isn't much room for adjustment. I did find that who you purchase from matters. I purchased one white, one gray and one beige from NY Lingerie and they were soooo short. I purchased four more from Amazon LLC and they were an inch longer in the band and about half an inch in the straps, so I'm returning the ones from NY Lingerie and keeping the ones from Amazon. Don't know why they would be different, but I even took pics.

NO yet YES. The body of the bras are and always have been primarily cotton fabric. The front is doubled layered fabric so you get more support and also better privacy. Say for those chilly days. Anyway I've been buying this bra since early 2000's. Probably 20 years. I used to only buy from bali and they ran once a year or two promotions and I'd buy 2-4 a year. I tried the same style double support in a brown nylon or poly like material but disliked the feel and ended up with a rash. I'm sensitive to my own sweat like a lot of folk are. NOW the elastics in the straps and banding for the bottom area is synthetics so that's where they add the other product listed. BUT the bra that keeps the girls in place and supported is 100% cotton. One note though. I now buy the grey only because all the other colors are not color fast and too light they do not hold their fresh color for long and start to fade upon the first few washes. Could be my hard water and detergents but I doubt it. I used to love to match my other undies with the natural beige and pink and white and do love them new they just don't hang in there looking nice for long. Even carefully cared for and washed with whites and like colors and in a mesh bag for kindness. But I'm such a fan of the grey even when my older bras is time to be replaced I kind of keep using them. Silly me. Straps over shoulders are NOT cotton and not cotton at all it's an elastic. I have not run into shorter straps or around measurements like some ladies have reported and I've been buying these for about 20 years.