A county is considering rasing the speed limit on a road because they claim that the mean speed of vehicles is greater than 40 miles per hour. A random sample of 15 vehicles has a mean speed of 41 miles per hour and a standard deviation of 5.2 miles per hour. At a= 0.05, do you have enough evidence to support the county's claim? Complete parts (a) through (d) below. (a) Write the claim mathematically and identify Ho and Ha- Choose the correct answer below. O A. Ho: H = 40 OB. Ho: H# 40 Ha: p # 40 Ha: H = 40 O C. Ho: us 40 OD. Ho: H 240 Ha : [ > 40 Ha: p