Question

question 10 (1 point) the speed of light is a constant so there is no need for scientists to ever check its validity. true false question 11 (1 point) all carbon atoms weigh 12.0107 amu. true false question 12 (1 point) the air we breathe is a homogeneous mixture. true false

Explanation:

• For Question 10: Scientists regularly conduct experiments to check fundamental constants like the speed of light for greater precision and to test the limits of physical theories.
• For Question 11: Carbon has isotopes with different masses. The 12.0107 amu is the average atomic - mass of carbon considering its isotopes.
• For Question 12: Air is a mixture of nitrogen, oxygen, carbon - dioxide, and other gases. It is not chemically pure and has variable composition, making it a heterogeneous mixture.

Answer:

Question 10: B. False
Question 11: B. False
Question 12: B. False