Identify the possible range of values and their data type for each of the above variables.

Outline how the yearly supply of water is calculated.

Construct the pseudocode that will calculate the annual bill for a household based on the information given above. You should introduce any new variables where necessary.

Identify three possible measures that customers could take to reduce their infrastructure charge.

Award up to [3 max]. 
Award [1] for correctly indicating type, and values expected, for each variable up to [3 max];

“MeterType”, String/char; “old”,”new”;
“WaterVol”, Integer; 0–999999;
“InfraCharges”, Currency/Float /Double; 184.32–204.80;

Making use of both the previous and new readings;
Calculating the difference between them;

Award up to [7 max] as follows:
Involving previous readings;
Calculation of water supplied [2] – allow [1] if correct apart from the reset;
Separate code for use of new meter;
Correct reduction of infrastructure charge [2] – allow [1] for an attempt to calculate this;
Calculation of final bill;

Example:

householdBill(OLD_WATER_IN, OLD_WATER_OUT)  // the previous 
                                            // meter readings
INFRACHARGE = 204.80
    if WATER_IN > OLD_WATER_IN // allows for possible 
                               // resetting of meter 
                               //reading to 0
        WATER_SUPPLIED = WATER_IN – OLD_WATER_IN
    else
        WATER_SUPPLIED = 1000000 – OLD_WATER_IN + WATER_IN
    end if

if METER_TYPE = "new" // possible reduction in sewage charges 
                      // if new meter is used
    if WATER_OUT > OLD_WATER_OUT
        WATER_RETURNED = WATER_OUT – OLD_WATER_OUT
    else
        WATER_RETURNED = 1000000 – OLD_WATER_OUT + WATER_OUT
    end if
    if WATER_RETURNED > 0.95 * WATER_SUPPLIED
        INFRACHARGE = INFRACHARGE * 0.9
    end if
end if

BILL = WATER_SUPPLIED * 1.9 + INFRACHARGE

Changing to a new meter (if they have an old one);
Not using the supplied water for watering the garden etc.;
Diverting rain water into the waste/sewage system;