Growth in the building of canals was made possible by: A. Production of reliable maps.
B. Improvements in engineering methods.
c. Improvements in steam engines.
D. Agreements with railroad companies.

B. Improvements in engineering methods.

evelyn "champagne" king

love come down

explanation:

the doctrine of nullification recommended that states living inside the union have the one-sided, inalienable ideal to void any law made by the national government that could be esteemed illegal.

the united states was shaped based on a general agreement among its individual states. hence, it is inferred that under the hypothesis of invalidation, since the states are the establishment of the union, they have the ability to referee and disprove unlawful laws.