Three friends are buying seashells at the gift shop on the beach. Melanie buys 2 seashells for $0.80
Rosi buys 5 seashells for $2.00. Carlos buys 4 seashells for $1.60. Use a graph to determine whether
the number of seashells and the cost have a proportional relationship. If so, what is the constant of
proportionality and what does it mean?

(b) suppose that consolidated power decides to use a level of significance of α = .05, and suppose a random sample of 100 temperature readings is obtained. if the sample mean of the 100 temperature readings is x⎯⎯ = 60.990, test h0 versus ha and determine whether the power plant should be shut down and the cooling system repaired. perform the hypothesis test by using a critical value and a p-value. assume σ = 5. (round your z to 2 decimal places and p-value to 4 decimal places.)