Goodness no, 8 weeks is far too young for rusk - have you seen what is them? - or weaning. Rusks are not recommended until at least 6 months because of the gluten
Weaning should not start now until 6 months this is because research has shown babies digestive system is not mature enough for solid food until this age. Baby should be able to sit unaided and if you wait until 6 months you dont have to make mush but can give pieces of soft fruit and vegetable, cooked
stacks of info out there about the age thing as well, but no way should you start at 8 weeks old, whether breast or formula fed. If baby is hungry up the milk they are having by either giving larger feeds or more frequent smaller feeds. Who said she 'should' be having a certain amount each day? your baby will eat what she needs not what other people say she should have :-). She may take more or she may even take less
http://www.eatwell.gov.uk/agesandstages/baby/w eaning/#cat227288
http://hcd2.bupa.co.uk/fact_sheets/html/baby_w eaning.html
Baby led Weaning is a wonderful way to wean
http://www.babycentre.co.uk/baby/startingsolid s/babyledweaning/
So much information out there :-)
hth