Answer:
12 12 12 12 12 12 12 12 12 1 2 12 12
okay, what numbers do you have to divide?
Answer:
We define the random variable X as the walking age and we are interested if American children learn to walk less than 15 months so then that would be the alternative hypothesis and the complement would be the null hypothesis.
Null hypothesis: 
Alternative hypothesis: 
And for this case the best answer would be:
H 0 : μ ≥ 15 vs. Ha : μ < 15
Step-by-step explanation:
We define the random variable X as the walking age and we are interested if American children learn to walk less than 15 months so then that would be the alternative hypothesis and the complement would be the null hypothesis.
Null hypothesis: 
Alternative hypothesis: 
And for this case the best answer would be:
H 0 : μ ≥ 15 vs. Ha : μ < 15
And the data given from the sample is:
represent the sample mean
represent the population deviation
represent the sample size
And the statistic would be given by:

22 and 27 is the answer. what else do you need??
Check the picture below.
now, keep in mind that ship B is going at 20kph, thus from noon to 4pm, is 4 hours, so it has travelled by then 20 * 4 or 80 kilometers, thus b = 80.
whilst the ship B is moving north, the distance "a" is not really changing, and thus is a constant, that matters because the derivative of a constant is 0.