What's the main differce between the two types of cones produced by conifer?
a. one is a monocot; the other is a dict.
b. one falls off the tree during the autumn; the other doesn't
c. one contains seeds; the other doesn't
d. one contains chlorophyll, the other doesn't

Higher temperature = molecules move around faster. and vice versa.

27. =3,500,000 x 4,000 = 14,000,000,000

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.