The average elevation of West Virginia is about 1,500 foot above sea level.()
A. average
B. elevation
C. foot
D. sea
In a microwave oven, radiation penetrates food and is then absorbed primarily by water molecules, caused heat to spread through the food.()
A. food
B. primarily
C. caused
D. the food
Physicians working in the field of public health are mainly concerned with the environmental causes of ill and how to eliminate them.()
A. working
B. concerned with
C. ill
D. how to