How did steam locomotives lower the cost of transporting raw materials and finished goods?
a. they cost nothing to run because they ran on steam.
b. they could transport many materials or goods at once.
c. they were uncomplicated and inexpensive to build.
d. they were safe and cut the chance of costly accidents.

Dominic and stacy each have a stamp collection. dominic has six fewer stamps than three times the number of stamps stacy has. dominic and stacy decide to give all of their stamps to their younger sister, mary. if stacy had s stamps, which expression represents the number of stamps that mary received? a. (3s − 18)(3s − 6) b. 2s − 18 c. 4s − 6 d. 4s − 18