Bird Migration Power P is the rate at which energy E is consumed per unit time. Ornithologists have found that the power consumed by a certain pigeon flying at velocity $v \mathrm{~m} / \mathrm{s}$ is described well by the function $P(v)=17 v^{-1}+10^{-3} v^3 \mathrm{~J} / \mathrm{s}$. Assume that the pigeon can store $5 \times 10^4 \mathrm{~J}$ of usable energy as body fat. (a) Find the velocity $v_{\text {pmin }}$ that minimizes power consumption.

Infection that weakens the heart muscle is called _______.

Identify each number as real, complex, pure imaginary, or nonreal complex. (More than one of these descriptions will apply.) -4

When a 0.80-kg crown is submerged in water, its apparent weight is measured to be 7.3 N. Is the crown pure gold?

How do negative signs on residuals affect the sum of squared residuals?

Look at the following statement:
numbers = [10, 20, 30, 40, 50]
a. How many elements does the list have?
b. What is the index of the first element in the list?
c. What is the index of the last element in the list?

Provide structures for the semicarbazone and the $2,4$-dinitrophenylhydrazone of citral.

Water permeability of concrete can be measured by letting water flow across the surface and determining the amount lost (in inches per hour). Suppose that the permeability index x for a randomly selected concrete specimen of a particular type is normally distributed with mean value 1000 and standard deviation 150. a. How likely is it that a single randomly selected specimen will have a permeability index between 850 and 1300? b. If the permeability index is to be determined for each specimen in a random sample of size 10, how likely is it that the sample mean permeability index will be between 950 and 1100? between 850 and 1300?

Which end of the muscle typically moves?

If you left a board lying on the grass for a few days, what would happen to the grass underneath the board? Why?

At what value of x does the quadratic function $f(x)=a x^{2}+b x+c, a \neq 0,$ have a stationary point? Under what conditions is the stationary point a local maximum or a local minimum?

Realtors use an index to compare housing prices in major cities. The housing price index values for several cities are given in the table below. Use the following formula to answer the question.

$$\underset{\text { (other town) }}{\text { price }}=\underset{\text { (your town) }}{\text { price }} \times \frac{\text { index of other town }}{\text { index in your town }}$$

$$\begin{array}{lc|lc} \text { City } & \text { Index } & \text { City } & \text { Index } \\ \hline \text { Atlanta } & 100 & \text { Las Vegas } & 115 \\ \text { Boston } & 146 & \text { Los Angeles } & 190 \\ \text { Chicago } & 105 & \text { Miami } & 161 \\ \text { Dallas } & 121 & \text { Phoenix } & 122 \\ \text { Denver } & 136 & \text { San Franciscol } & 172 \end{array}$$

For a house valued at $\$ 600,000$ in Boston, find out the price of a comparable house in Los Angeles.

Evaluate each expression. a. 2^4 b. 5^3 c. 8.3^2 d. 1^9 e. 13^1 f. 56.8^0 g. 10^5 h. 100^2 i. 0^12 j. eleven squared k. one and three-tenths cubed l. seven squared times two cubed m. three to the fifth power n. four squared cubed

Suppose we have a repository of 1000 documents, and we wish to build an inverted index with 10,000 words. A block can hold ten word-pointer pairs or 50 pointers to either a document or a position within a document. The distribution of words is Zipfian; the number of occurrences of the $i$ th most frequent word is $100000 / \sqrt{i}$, for $i=1,2, \ldots, 10000$.

a) What is the averge number of words per document?

b) Suppose our inverted index only records for each word all the documents that have that word. What is the maximum number of blocks we could need to hold the inverted index?

c) Suppose our inverted index holds pointers to each occurrence of each word. How many blocks do we need to hold the inverted index?

d) Repeat (b) if the 400 most common words ("stop" words) are not included in the index.

e) Repeat (c) if the 400 most common words are not included in the index.