You are the Billing Manager at ABC Electricity Distribution Board Ltd$.$ You job is to maintain monthly electricity bills of various consumers of your company and give them subsidies as applicable. You need to maintain a doubly linked list that stores the records of electricity bills having the following attributes: $\{$Bill$\_$Number, Consumer$\_$Details, Month, Year, Units$\_$Consumed, Bill$\_$Amount$\}.$ The Consumer$\_$Details include: $\{$Consumer$\_$ID$,$ Name, Age, Address, Gender$\}.$ Please answer the following questions:

Create structure definitions required for storing a record of electricity bill $($struct electricity$\_$bill$)$ and a record of consumer details $($struct consumer$).$ Choose most appropriate datatypes so as to minimize the number of bytes required to store each attribute. $[$Marks will be deducted if datatypes are not the most appropriate ones$].$ Also create structure definitions for the header and the node separately as required for creating a doubly linked that can store records of electricity bills. $12M$

Write a function readDetails$()$ that takes the input: number of billing records from the user and reads details of that many number of billing records from the user and stores them in a doubly linked list. You should NOT read Bill$\_$Amount for each record from the user. However, it must be calculated using Units$\_$Consumed as per the slab rates given below:

$0-100$ units: Rs $5$ per unit

$101-200$ units: Rs $10$ per unit

$200$ and above: Rs $15$ per unit

For example, if Units$\_$Consumed $=250,$ then Bill$\_$Amount $=100**5+100**10+250**16=$$$250.$

The function must return the doubly linked created above. DON'T CREATE ANY ADDITIONAL FUNCTIONS. No marks will be awarded if you create additional functions. Also, the design of your doubly linked list must adhere to the specifications give above. Any deviation will incur a penalty or awarded zero. $16M$

Now, you want to subsidize the electricity bill for senior citizens $($age $>65).$ Write a function subsidizeBills$()$ which takes the above doubly linked list of billing records as input and recalculates the Bill$\_$Amount for each record after applying the subsidy of $50\%$ for senior citizens, wherever applicable. $8M$