# Tutor profile: Rachel N.

## Questions

### Subject: Pre-Algebra

Convert the following into scientific notation with 2 significant figures. $$ 162,870 $$

We need the answer to have 2 significant figures. In this case, we move the decimal 5 places to the left to get to 1.6. Since we moved 5 places, we need to write $$ 10^{5} $$, so we have $$ 1.6 \cdot 10^{5} $$ We do not round up in this case to $$1.7$$ because the next decimal to the right is not 5 or greater.

### Subject: Biology

What are the main stages of mitosis?

1. Interphase: the growth of the cell and replication of DNA as the cell prepares to divide. 2. Prophase: the nuclear membrane dissolves and chromatin turns into chromosomes. 3. Metaphase: Chromosomes and their copies line up along the center of the cell. 4. Anaphase: Identical chromosomes separate and move to opposite poles of the cell. 5. Telophase: A nuclear membrane forms around the two sets of chromosomes and the cell begins to pinch. 6: Cytokinesis: The cell officially splits at the membrane, forming two new daughter cells that are genetically identical.

### Subject: Algebra

Solve for x using the quadratic formula. $$x^{2} + 5x + 6 $$

The quadratic formula is $$ \frac {-b +/- \sqrt{b^{2} - 4ac}}{2a} $$, so we need to plug in the values of a=1, b=5, and c=6 based on $$ ax^{2} + bx +c $$. Once we plug in the numerical values, we get $$ \frac{-5 +/- \sqrt{5^{2} - 4(1)(6)}}{(2)(1)} $$ Simplify: $$ \frac{-5 +/- \sqrt{25-24}}{2} $$, then we get $$ \frac{-5 +/- \sqrt{1}}{2} $$ We can split the answer into two separate parts: $$ \frac{-5 + 1}{2} $$ and $$ \frac{-5 - 1}{2} $$ After simplifying both answers, we get -2 and -3, so $$x=-2, -3 $$

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