<span>The correct answer to this question is a line graph. If Rob needs to create a graph that is able to display the combination of two different values - in this case, level to which the salt has dissolved and time taken - and he needs to have more than one result included, then a line graph is the way to present this.</span>
<span>How can a mutation in a DNA base sequence cause a change in a trait?</span>
Answer:
The heart valves
Explanation:
The heart valves prevent blood from flowing in the wrong direction in the heart. The valves are held in the proper place because of the chordae tendinae.