Answer:
Changes in environment, food source changes and disease?
Explanation:
I dont know what the answer choices are
<span>NaCn contains an Na+ ion and a CN- negative ion, so it has an ionic bond. The CN ion is formed by a covalent bond of the carbon and nitrogen, so it also has a covalent bond. Therefore, the answer is NaCN.</span>
Answer:
-1, -4
Explanation:

Factoring, you get:

To find what x can be, you need to realize what could make this equation true. To set the left side equal to 0, either one of the terms in parentheses must be equal to 0. To do that, x must be the negative of the other term, so that they can cancel each other out. Therefore, x is -4 and -1. Hope this helps!