Cart Data Sub Categories

Greetings,
I see finally the new WP REST API Support Docs are published live now.
I would like to know as you guys said in the old post, How can i get all the sub categories of a particular category via API?

http://localhost/demo/wp/api/v1.2/ is a HTACess via original wp-json

http://localhost/demo/wp/api/v1.2/products/categories/13

https://ww.wp.xz.cn/support/topic/wc-api-angularjs-cod-basic-features?replies=24#post-8419128

i tried http://localhost/demo/wp/api/v1.2/products/categories/13?display=subcategories
but it doesn’t work, can u tell me how to do that?

Also is there a way we can see cart data in API?

Help appreciated.

Thanks!

https://ww.wp.xz.cn/plugins/woocommerce/