Estimate the number of bacteria

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Microbiologist estimating the number of bacteria in a sample that contains bacteria that do not grow well on solid media may
use a statistical technique called the nu most probable number (MPN) method. Each of five tubes of nutrient medium receives
10 ml of the sample. A second set of five tubes receives 1 ml of sample per tube, and in each of the a third set of five tubes,
only 0.1 ml of sample is placed. Each tube in which bacterial growth is observed is recorded as a positive, and the numbers
for the three groups are combined to create a triplet such as 5-2-1, which means that five tubes receiving 10 ml of sample
showed bacterial growth, only two tubes in the 1-ml group showed growth,and only one of the 0.1-ml group was positive. A
microbiologist would use this combination-of-positives triplet as an index in the table like Table 1 to determine that the most
probable number of bacteria per 100 ml of the sample is 70, and 95% of the samples yielding this triplet between 30 and 210
bacteria per 100 ml. This information is stored in a file, mpm.txt, that has the same structure as Table 1.
(a) Define a type, MPNInfo, that represents each record in the file containing information on bacterial concentrations for
Most Probable Number. Each of these records is made of a string combination-of-positives as described above, an
integer representing the MPN Index/100 ml, the lower number of bacteria per 100 ml, and upper number of bacteria per
100 ml. [4]
Table 1: Table of Bacterial Concentrations for Most Probable Number Method
95% Confidence Limits
Combination of
Positives MPN Index/100 ml Lower Upper
4-2-0 22 9 56
4-2-1 26 12 65
4-3-0 27 12 67
4-3-1 33 33 77
4-4-0 34 16 80
5-0-0 23 9 86
5-0-1 30 10 110
5-0-2 40 20 140
(b) Define a function LoadMpnTable that uses a variable of type MPNInfo to load the MPN table from a stored file, mpn.txt,
into four parallel arrays:
– an array of strings combOfPositives
– three integer arrays - mpn, lower and upper
Your function must return the actual array size (number of records read from the file)
(c) Define a function Search that takes as arguments: the actual size of arrays, the arrays read in (b):
– an array of strings combOfPositives
– three integer arrays - mpn, lower and upper
and a combination-of-positives triplet and finds its index in the array combOfPositives, and produces the following:
– if the target is found, this index is used to generate a message. For example, using information in Table 1, if the
triplet given is 5-2-1, the following message is produced:
For 5-2-1, MPN = 70, 95% of samples contain between
30 and 210 bacteria / ml
– if the target is not found in the array, the following message is produced:
The combination 5-2-1 does not exist
(d) Write a driver program that tests the functions written above

What I have tried:

i dont understand yet how to do the code, please assist.