It is plain flour, but with a medium gluten content.
Flour can have a high gluten content - (strong flour) and this sort of flour is best for bread making, or a low gluten content in which case it is best for pastry and cakes (if you add baking powered to low gluten flour - this is sold as self raising flour).
A multi purpose flour will have a medium gluten content and thus can be used for both bread and cake baking it is a compromise product.
Yes, it generally won't matter.
no it's not all purpose flour..
yes enriched flour can be substituted for all purpose flour in a cake
all purpose flour has bleach in it, therefore when you eat anything made with all purpose flour you are eating bleach.
There is no difference between plain flour and all-purpose flour. They are one and the same. All-purpose (plain) flour does not contain the salt and baking soda that self-rising flour has.
It is bread flour.
No. Some cake flours contain corn starch. Pastry flour, or all-purpose flour, does not.
yes. They are the same thing. Plain flour is an Australian term where all-purpose is the American.
all purpose flour
Yes. All-purpose flour and unbleached flour are usually the same thing. Just be sure that the package doesn't say something like 'self rising', 'bread flour', or 'cake flour' - those ARE NOT all-purpose flour.
Hong Kong flour is a type of all-purpose flour that is highly bleached.
All flour is unsifted until you sift it. Al purpose included.