Answer: A
Explanation:Convection currents in the mantle Mantle convection is the very slow creeping motion of Earth's solid silicate mantle caused by convection currents carrying heat from the interior to the planet's surface. The Earth's surface lithosphere rides atop the asthenosphere and the two form the components of the upper mantle.
Answer: B
Explanation: Hemoglobin is a protein in red blood cells that acts as the vehicle for oxygen and carbon dioxide from the lungs to tissues and vice-versa.
What is considered normal Hemoglobin levels vary throughout one's life, from childhood to adult life and in older adults. It even varies between women and men. In women, it also varies depending on whether they are pregnant or not.
When hemoglobin does become less than normal, it results in anemia, a condition accompanied by fatigue. Because the athlete does not have this symptom, he is not suffering from anemia, and so there is no cause for concern. Although the athlete's hemoglobin level has reduced, the absence of fatigue indicates that it is not lower than normal.
They both weigh the same. Since they both weigh 2g :)
