1) Resin is a substance that _____in water.

2) _____hardiness, daylilies can be cultivated particularly easily.

3) A biologist does not merely describe organisms, but tries to learn _____act as they do.

4) Vaporization in connection with general _____ has a marked effect on long – term climate.

5) The oldest city in the state, _____ .

6) Mary Edmonia Lewis, a sculptor who studied at Oberlin College, was _____ by Hrrietffosmer.

7) Even though rhubarb is a vegetable, _____ as a dessert.

8) Elizabeth Cabot Agassiz, _____ of Radeliffe College, had worked as both an educator and a naturalist.

9) _____ ever developed was celluloid, a combination of natural camphor and cellulose nitrate.

10) Often the design of a scholarly investigation _____ by the question it is addressing.

11) In the nineteenth century, Samuel Gridley Howe founded the Pekins School for the Blind, _____ for children in Boston, Massachusetts.

12) Early forms of life on Earth, _____ in the absence of oxygen, required elements such as sulfur instead.

13) People in prehistoric times created paints by grinding materials such as plants and clay into powder _____.

14) Often very annoying weeds, _____ and act as hosts to many insect pests.

15) Starting around 7000 B. C., and for the next four thousand years, much of the Northern Hemisphere _____ temperatures warmer than at present.