B. 6(18c + 16r) = t
This shows her, in the parenthesis, exactly how many each shop should get.
C. 432 Carnations.
192 Roses
Simply multiply the bunches by the number in a bunch
D. Jake has 2.25 the number of carnations as roses. So he could use 9 carnations and 4 roses per grouping and that would give him an equal number with none left over.