Angela bought gifts for her friends, and each gift cost $10. Let y represent the total cost and x represent the number of gifts. Write an equation to represent the proportional relationship between the total cost and the number of gifts she bought. (4 points) a
y = 9x

b
y = 10x

c
y = one-tenth x

d
y = one-ninth x

Rachel is studying the population of a particular bird species in a national park. she observes every 10th bird of that species that she can find in the park. her conclusion is that the birds living in the park who belong to that species generally feed on insects. rachel's sample is . based on the sample she picked, rachel's generalization is . reset next