Select the correct answer. Calcium carbonate is a compound that is used to make chalk for drawing on rocks or pavement. One molecule has one atom of calcium (Ca), one atom of carbon (C), and three atoms of oxygen (O). Which is the correct way to write the chemical formula for calcium carbonate? A. 3CaCO B. Ca3CO C. CaCO3 D. Ca3C3O3

What kind of interaction is depicted in the image? a. intraspecific, direct b. intraspecific, indirect c. interspecific, direct d. interspecific, indirect e. invasion

An ecosystem is shown in the illustration. assume that human activities have led to a decrease in the number of eagles. a virus attack on rabbits has led to a decrease in their population in the ecosystem. which two sentences describe likely effects on the ecosystem? 1. there’s an increase in the number of snakes and insects and a decrease in the number of frogs. 2. there’s an increase in the number of snakes and insects, and the storks face increased competition for food. 3. there’s an increase in the number of storks and a decrease in the number of snakes and insects. 4. there’s an increase in the number of frogs and a decrease in the number of storks and insects. 5. there’s a decrease in the number of snakes, insects, and frogs.

How do you work out 21.3-8= show your working. plz