Which expression should you simplify to find the 90% confidence interval, given a sample of 90 people with a sample proportion of 0.25?
0.25(1-0.25)
A. 0.25 + 1.645. V
90
B. 0.25 +
1.645-0.25
90
0.25(1–0.25)
O C. 0.25 +1.645. V
90
D. 0.25 +90
0.25(1-0.25)
1.645

Starting at home, emily traveled uphill to the hardware store for 606060 minutes at just 666 mph. she then traveled back home along the same path downhill at a speed of 121212 mph. what is her average speed for the entire trip from home to the hardware store and back?