You do not start saving money until age 46. On your 46th birthday you dutifully invest​ $10,000 each year until you finish your deposits when you reach the age of 65​ (you make the last deposit on your 65th​ birthday). The annual interest rate is 8​% that you earn on your deposits. Your brother starts saving​ $10,000 a year on his 36th birthday but stops making deposits after 10 years. He then withdraws the compounded sum when he reaches age 65. How much more money will your brother have than you at age​ 65?

The leading producer of cell phone backup batteries, jumpstart, has achieved great success because they produce high-quality battery backups that are not too expensive. even so, another company that produces lower-quality batteries at the same price has also achieved some success, but not as much as jumpstart. also, in general, the price of backup batteries has declined because of economies of scale and learning. in addition, jumpstart has added complementary assets, such as a carrying case. considering all of these factors, the backup battery industry is most likely in the introduction stage. growth stage. shakeout stage. maturity stage.

Who is better at multi-tasking? in business, employees are often asked to perform a complex task when their atten-tion is divided (i.e., multi-tasking). human factors (may 2014) published a study designed to determine whether video game players are better than non–video game play-ers at multi-tasking. each in a sample of 60 college stu-dents was classified as a video game player or a non-player. participants entered a street crossing simulator and were asked to cross a busy street at an unsigned intersec-tion. the simulator was designed to have cars traveling at various high rates of speed in both directions. during the crossing, the students also performed a memory task as a distraction. two variables were measured for each student: (1) a street crossing performance score (measured out of 100 points) and (2) a memory task score (measured out of 20 points). the researchers found no differences in either the street crossing performance or memory task score of video game players and non-gamers. “these results,” say the researchers, “suggest that action video game players [and non-gamers] are equally susceptible to the costs of dividing attention in a complex task”

Using a cps-sample of 7,440 individuals, you estimate the following regression: = 20.91 - 2.61 x female where female is a binary variable that takes on the value of 1 for females and is 0 otherwise. the standard error on the coefficient on female is 0.25. the 95% confidence interval for the gender wage gap, or the amount that females earn less, is: a) [-3.10, -2.12] b) [18.30, 23.52] c) [-3.02, -2.20] d) [-1.96, -1.64]