# Tutor profile: Sophia D.

## Questions

### Subject: Chemistry

What are the oxidation states of the elements in the following reaction? 2Mg(s) + O2 (g) --> MgO (s)

The oxidation state of an uncombined element (an element by itself) is zero, so the oxidation state of the reactants Mg(s) and O2(g) are zero. In MgO, the oxidation state of Mg is +2 and the oxidation state of oxygen is -2.

### Subject: Biology

What is the difference between aerobic and anaerobic respiration?

Aerobic respiration is the pathway that a cell takes when there is oxygen present. One molecule of glucose will go through glycolysis, the Krebs cycle and oxidative phosphorylation to produce about 38 ATP. On the other hand, when the cell does not have access to oxygen, it will use the anaerobic pathway, which consists solely of glycolysis and makes a total of 2 ATP.

### Subject: Calculus

A ball is thrown in the air. It's height (in feet) at a given time t is h(t)=2+8t-2t^2. What is it's maximum height?

To find the time t where the ball is at its maximum height, first take the derivative of h(t) and equate to zero h'(t)=8-4t 8-4t=0 4t=8 t=2 Now that we know the time at which the maximum occurs, plug t=2 into h(t) to find the ball's height at that time. h(2)=2+8(2)-2(2)^2=2+16-8=10 So the maximum height of the ball is 10 feet.

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