Solve the Problem $\frac { \mathrm { dy } } { \mathrm { dt } } = - 0.7 \mathrm { y }$

question 31

Multiple Choice

Solve the problem.
-In a chemical reaction, the rate at which the amount of a reactant changes with time is proportional to the amount present, such that $\frac { \mathrm { dy } } { \mathrm { dt } } = - 0.7 \mathrm { y }$ , when $\mathrm { t }$ is measured in hours. If there are $78 \mathrm {~g}$ of reactant present when $t$ $= 0$ , how many grams will be left after 4 hours? Give your answer to the nearest tenth of a gram.

• A) 4.7 g
• B) 2.4 g
• C) 0.1 g
• D) 7.1 g

---

Definitions:

Other Comprehensive Income

Income that includes all changes in equity from non-owner sources, such as foreign exchange adjustments or unrealized gains/losses on certain investments, not included in net income.

Vertical Analysis

A method of financial statement analysis in which each entry for each of the three major categories of accounts (assets, liabilities, and equity) is represented as a proportion of the total account.

Net Sales

The amount of sales revenue remaining after deducting sales returns, allowances, and discounts.

Comprehensive Income

The change in equity of a company during a period from transactions and other events, excluding any owner contributions and distributions.