You are interested in calculating whether emeralds are significantly more expensive than rubies. Match the correct null and alternative hypotheses for this hypothesis test.

a. Null hypothesis
b. Alternative hypothesis

a. There is a significant difference in the price of emeralds and rubies
b. Rubies are significantly more expensive than emeralds
c. There is no difference in price between emeralds and rubies.
d. Emeralds are significantly more expensive than rubies