Based on these observations do you consider that Activity Level of individuals is a variable that affects the relationship between exercise intensity and heart rate and should be accounted
for when examining this relationship? Should it be a controlled variable?

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus

c. is the correct answer

they have identical fossils of organisms that have evolved over time.

both have animal fossils preserved in them due to weathering and erosion.

they contain different fossils because life on earth has changed through time.

the fossils in them were formed on the surface of earth due to exposure to sunlight.

not always but somethings can be reproduced in a laboratory.