Which of the following explains why most elements in the periodic table have a decimal number for their atomic mass?
a. most elements have different isotopes.
b. most elements have different number of electrons.
c. most elements have different numbers of protons in the nucleus.
d. most elements are not found in nature.

What are the types of mutations, and how does each alter the encoded protein? college level answer

State officials are considering constructing a road through a forested wilderness area. this action will likely affect the forest ecosystem in various ways. part a: predict how the construction of a road could negatively affect plants and animals in that ecosystem. (3 points) part b: describe one way that the construction of a road could have a positive impact of the forest ecosystem. (1 point)

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the