7.During the Pleistocene glacial periods _____ portions of the Earth where plant and animal life flourished making it possible for people to subsist.

(A)the

(B)it was

(C)there were

(D)have there been

8.The photographs of Carrie Mae Weems,in which she often makes her family members _____,are an affectionate and incisive representation of the African American experience.

(A)are her subjects

(B)her subjects

(C)are subjects

(D)which her subjects.

9.Hubble's law states that the greater the distance between any two galaxies,_____ is their relative speed of separation.

(A)the greatest

(B)the greater

(C)greater than

(D)as great as

10.The onion is characterized by an edible bulb composed of leaves rich in sugar and a pungent oil,_____ the vegetable's strong taste.

(A)which the source of

(B)that the source is

(C)the source of

(D)of the source is

11.A regional writer with a gift for dialect,_____ her fiction with the eccentric,comic,but vital inhabitants of rural Mississippi.

(A)and Eudora Welty is peopling

(B)Eudora Welty peoples

(C)because Eudora Welty peoples.

(D)Eudora Welty,to people.

12.Relative humidity is the amount of water vapor the air contains at a certain temperature _____ with the amount it could hold at that temperature.

(A)to compare

(B)compared

(C)comparing

(D)compares