An economist wants to estimate the mean per capita income (in thousands of dollars) for a major city in texas. he believes that the mean income is $20.4, and the standard deviation is known to be $8.8. how large of a sample would be required in order to estimate the mean per capita income at the 98% level of confidence with an error of at most $0.54$? round your answer up to the next integer.

The box plots show the average speeds, in miles per hour, for the race cars in two different races. which correctly describes the consistency of the speeds of the cars in the two races?

At wind speeds above 1000 centimeters per second (cm/sec), significant sand-moving events begin to occur. wind speeds below 1000 cm/sec deposit sand and wind speeds above 1000 cm/sec move sand to new locations. the cyclic nature of wind and moving sand determines the shape and location of large dunes. at a test site, the prevailing direction of the wind did not change noticeably. however, the velocity did change. fifty-nine wind speed readings gave an average velocity of x = 1075 cm/sec. based on long-term experience, σ can be assumed to be 245 cm/sec. (a) find a 95% confidence interval for the population mean wind speed at this site. (round your answers to the nearest whole number.) lower limit cm/sec upper limit cm/sec

In terms of x, find an expression that represents the area of the shaded region. the outer square has side lengths of (x+5) and the inner square has side lengths of (x-2), as shown. area: a1 x + a2 square units submit