Once again, consider Leo and Mark, who can produce cookies and tea using only 10 labor hours each.Leo can produce 60 cookies if he produces no tea; he can produce 20 units of tea if he produces no cookies.Mark can produce 40 cookies if he produces no tea; he can produce 16 units of tea if he produces no cookies.

If in autarky each producer spends half of his time producing cookies and the other half producingtea, then in autarky Leo would produce __________ units of tea.