You can refer to the the following attachment for the answers you are looking for :D
A few points to be kept in mind :-
Oxalic acid is an organic acid and is mainly found in organic substances like green leafy vegetables, fruits, normal vegetables, etc. I don't know if it is also found in Nuts though.
Pottasium Hydroxide(KOH) and Caustic Soda, a.k.a, Sodium Hydroxide(NaOH) are very much chemically similar. Hence, they can be used interchangebly in experiments.
Lactic Acid is produced due to the breaking down of Lactose Sugar present in milk by the bacteria Lacto Bessilus which then turns this milk into curd.
Answers & Comments
You can refer to the the following attachment for the answers you are looking for :D
A few points to be kept in mind :-
HOPE THIS HELPS : >
Answer:
1. = b
2. = c
3. = d
4. = g
5. = f
6. = a
7. = e