Answer:
B. It is reasonable to use the? z-interval procedure in this case? since, although the sample is small? (size less than? 15), the variable under consideration is very close to being normally distributed.
Step-by-step explanation:
answer b is considered to be correct because we know that the population is normal and the standard deviation is known, which allows using the interval z, the answer A is not correct because although the option to use the interval z is given, which is correct, the large sample is not favored, the answer C and D are incorrect because they both reject the use of the z interval and in d it is further rejected that although there is a normal distribution the sample is not, which is false
Common difference = -16-(-20) = 4
nth term = -20+(n-1)4
It is given in the question that,

Since we have the value of r given, so we have to use the formula to find the nth term of the geometric progression, which is

Substituting the values of a and r, we will get

So the correct option is the third option .
It is b 4/3+2/3 is 6/3 and 6/3 divided by 1/3 is 2/3x