Question

1. an invoice;
2. foreign trade
3. a statement
4. a receipt
5. a quotation
6. an estimate
7. a counter - proposal

a) an exchange of goods and services between nations;
b) the price given for goods or a piece of work;
c) a letter where the customer tries to get better terms;
d) a bill for goods sent or work done;
e) an approximate calculation of the cost of something;
f) a document that proves you have paid for some goods;
g) a list of amounts paid and still owed, sent every month.