During which geological period did the order $Gnetales$ of gymnosperms evolve?

"Monkey's puzzle" is a common name for:

Which of the following is a fossil plant?

Where are prokaryotic autotrophic symbiotic nitrogen fixers found?

What is correct for conifers?
$I$ - Leaf is like a needle,$II$ - Thick cuticle,$III$ - Thin cuticle,$IV$ - Sunken stomata,$V$ - Stomata absent

How many archegonia develop on one gametophyte of Cycas?