Braden wants to compare the types of ducks in two nearby ponds. He collected two samples using the following criteria. For sample 1, he counted the types of ducks on Walden Pond from 6 A.M. to 9 A.M. For sample 2, he counted the number of Mallard ducks that were on Brook’s Pond from 12 P.M. to 3 P.M. What would improve Braden’s plan? Check all that apply.