Choose the equivalent system of linear equations that will produce the same solution as the one given below.

6x + 2y = −6
3x − 4y = −18

12x + 4y = −12
15x = −30
8x + 4y = −4
14x = −10
6x − 8y = −36
−6y = −42
6x − y = −15
3y = 9

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