An NBA trainer wants to know if his stretching routine is helping the players on his team jump higher. He records the average height jumped for 8 players before completing his stretching routine, and then again after they have stretched. What is the parameter? Group of answer choices dbar = the true sample mean difference in jump height mu_d = the true sample mean difference in jump height dbar = the true population mean difference in jump height mu_d = the true population mean difference in jump height

a. mu_d = the true population mean difference in jump height

Step-by-step explanation:

In statistical parlance, observations used for a study could either be randomly chosen points or members of a large group or population, this small chosen observation obtained from a larger group is called the sample, the statistical measures or characteristic of such group is called statistic; while statistical characteristic, computations or measurement of the entire group of observations is called the parameter.

Mean of sample are usually represented with a bar sign on top such as (xbar) ; while mean of a population is represented as μ.

80 the answer is 80

step-by-step explanation:

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58