Answer:
The value of the test statistic is 
Step-by-step explanation:
The formula for the test statistic is:
In which X is the statistic, 
is the mean, 
is the standard deviation and n is the number of observations.
In this problem, we have that:
So
The value of the test statistic is
Answer:
550km/h
Step-by-step explanation:
v (speed) = d/t
v = 1375/2.5
v =550
-24a²- 6a +9 = - 3(8a² +6a - 9)
8a² +6a - 9 =0
x=(-b +/-√(b² - 4ac))/2a
x = (-6 +/-√(36+4*8*9) /(2*8) = (-6 +/-√(324) /16 = (-6 +/-18)/16
x1 = (-6 +18)/16 = 0.75
x2 = (-6 -18)/16 = - 1.5
-24a²- 6a +9 = - 3(8a² +6a - 9) = -3(a - 0.75)(a + 1.5)
