38. Round off each of the following numbers to two significant digits, and express the result in standard scientific notation.
a. 1,566,311
c. 0.07759
b. 2.7651 X 10-3
d. 0.0011672

Ibelieve the answer is d

The correct answer would be b) volume versus temperature, because they are also directly proportional.

The phase where ice changes directly to gas is called sublimation 

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.