I believe the answer would be B.
Answer:
Explanation:
B. có nhiều hệ sinh thái khác nhau trên trái đất. mỗi hệ sinh thái có một đặc tính riêng và chúng có thể kết nối, tác động qua lại với các hệ sinh thái khác
Answer:
Water is important in chemical weathering because most substances dissolve in water.
The process of dissolving breaks up the minerals in the rock into small pieces. The small pieces mix with water to form.
Acids are also agents of chemical weathering and cause more chemical weathering than pure water does.
Enzymes are biological catalysts. Catalysts lower the activation energy for reactions. The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy.
Answer:
There are 64 fish, 8 ducks and 4 turtles.
Explanation:
From the question, there can be from 2 to 99 fish in the pond. However, there cannot be fractions in the number of fish, ducks or turtles. Hence, the number of fish must have both of a perfect square and perfect cube. The perfect squares from 2 to 99 are 4, 9, 16, 25, 36, 49, 64 and 81. The perfect cubes from 2 to 99 are 8, 27 and 64. Since only 64 fits both criteria, the number of fish is 64. The number of ducks is the square root of number of fish, which is the square root of 64. The square root of 64 can be either positive 8 or negative 8. However, there cannot be negative numbers, so there are 8 ducks in total. The number of turtles is the cube root of the number of fish, which is the cube root of 64 and it is 4.