Question:
Based on the premise "But the basic premise of the IRA rules is that people with income are taxed on their earnings.", can we conclude that "People are taxed based on their earnings."?
****
Answer:
yes

Question:
Based on the premise "The boats carrying the banana crops also fostered the beginnings of the tourist trade.", can we conclude that "Jamaica has never allowed tourists to enter the country by boat."?
****
Answer:
no

Question:
Based on the premise "How do we know this?", can we conclude that "Are we sure of this?"?
****
Answer:
yes