Choose the best answer. What percentage of the world's population lives in developing countries? (a) 34 percent (b) 50 percent (c) 66 percent (d) 83 percent

X is a discrete random variable where $X \sim \mathrm{B}(n, p), \mathrm{E}(X)=12$ and $\operatorname{Var}(X)=3$. Find n and p.

Solve the following exercise.

Show that $\tan x>x$ for $0<x<\pi / 2$. [Hint: Show that $f(x)=\tan x-x$ is increasing on $(0, \pi / 2)$.]

A $2.0 - \mu \mathrm { F }$ capacitor and a $4.0 - \mu \mathrm { F }$ capacitor are connected in series across a 1.0-kV potential. The charged capacitors are then disconnected from the source and connected to each other with terminals of like sign together. Find the charge on each capacitor and the voltage across each capacitor.

Use the integration capabilities of a graphing utility to approximate the work done by a press in a manufacturing process. A model for the variable force F (in pounds) and the distance x (in feet) the press moves is given.

Show that sinh(-x) = -sinh(x).

In the morning, the temperature at the top of Mt. Washington in New Hampshire was -10F. Use the conversion formula $C=\dfrac{5}{9}(F-32)$ to find the temperature to the nearest Celsius degree. A. $-48$
B. $-28$
C. $-23$
D. $-12$

Jason cycled for 3 hours. He cycled 7 1/2 miles each hour for the first two hours and the distance he cycled for the third hour was 1/4 of the total distance he cycled in 3 hours. What was the total distance Jason cycled in 3 hours?

What are all possible results of the expression (n % 5), where n is a positive integer variable?

Find $f^{\prime}(x)$ and the equation of the line tangent to the graph of fat the indicated value of x. Find the value(s) of x where the tangent line is horizontal. $f(x)=(2 x+8)^{1 / 2} ; \quad x=4$

Stephanie Kwolek invented

A. body armor made of nylon.

B. a type of synthetic fiber.

C. steel alloy used in textiles.

D. medical-grade nylon.

E. polymers.

Two equal-value capacitors are connected in series. At any frequency, the total reactance is (a) one-half the reactance of each capacitor (b) equal to the reactance of each capacitor (c) twice the reactance of each capacitor

In response to the increasing weight of airline passengers, the Federal Aviation Administration (FAA) in 2003 told airlines to assume that passengers average 190 pounds in the summer, including clothing and carry-on baggage. But passengers vary, and the FAA did not specify a standard deviation. A reasonable standard deviation is 35 pounds. Weights are not Normally distributed, especially when the population includes both men and women, but they are not very non-Normal. A commuter plane carries 22 passengers. What is the approximate probability that the total weight of the passengers exceeds 4500 pounds? Use the four-step process to guide your work. (Hint: To apply the central limit theorem, restate the problem in terms of the mean weight.)

How does the electric potential change if the distance r away from the source of the field increases?