Question

6
multiple choice 1 point
which sentence from the article best represents the central idea?
○ to test his theory, dr. fish teamed up with engineers from duke university and the u.s. naval academy.
○ the secret seems to lie in the way tubercles break up the flow of air and water, creating tiny vortices, or swirls.
○ because the attachments decrease drag and delay stall, these turbines keep turning even at low wind speeds.
○ dr. fish loves the idea of using nature’s designs to invent new technologies.

7
multiple choice 1 point
read the sentences from paragraph 13.
one problem for turbines is that wind is not constant. even in gusty places like north dakota and kansas, strong winds do not blow all the time.
what is the meaning of constant as it is used above?
○ steady

Explanation:

Question 6

To find the central idea, we analyze each option:

• The first option is about testing a theory (a method), not the main idea.
• The second option explains a scientific mechanism (how tubercles work), not the overarching idea.
• The third option describes a technical benefit of turbines, which is a detail.
• The fourth option states Dr. Fish’s core idea of using nature’s designs for new technologies, which is the central theme connecting the other details (testing, how tubercles work, turbine benefits relate to this idea).

The context is about wind not being constant—even in gusty areas, strong winds don't blow all the time. So "constant" means unchanging or steady (consistent in occurrence).

Answer:

D. Dr. Fish loves the idea of using nature’s designs to invent new technologies.

Question 7

(Note: Since the options for the meaning of "constant" are not fully visible, assuming the common context: the sentence says wind isn't constant (even in gusty places, strong winds don't blow all the time), so "constant" here means steady (unchanging, continuous). If the option "steady" is present, that's the answer. For example, if the options include "steady" as an option (let's assume the option is A. steady), then: