Answer:
8,185,320 different leadership structures
Step-by-step explanation:
Since the order at which the members of the committee are chosen matters, this is a permutation of 4 out 55 people and it is given by:

8,185,320 different leadership structures are possible.
The top half is called the numerator.
The bottom is called the denominator.
Answer:
a) Cluster sampling
Step-by-step explanation:
<em>Since here the population is divided into many groups (cluster) and one of these groups is taken as a sample. This type of sampling is called Cluster Sampling.</em>
Further,
In Cluster Sampling the population is distributed into a distinct group called cluster and clusters are chosen as a sample then it is Cluster Sampling.
Multistage Sampling is a complex form of Cluster Sampling. In this sampling population is divided into a different group then one or more groups are randomly selected then again that selected group is divided into a different small group and again one or more these small groups are randomly selected as sample. This process is done many times.
If the sampling is done by any criteria then this type of sampling method is called Systematic Sampling. Like observer is taken every 5th unit as a sample.
If the whole population is divided into many groups(strata) such that between the group units are heterogeneous and within the group units are homogeneous then units are randomly selected from these groups. This type of sampling is called Stratified Sampling.
Absolute value can never be negative
Absolute value: | |
| 1 | ( ) 5
1 ( ) 5
1 < 5
Hope this helped:)