I need assistance creating a decomposed lower level data flow diagram $($DFD$)$ for the following requirements for a customer posting payment to a store charge account. This is done by scratch using Microsoft Visio and based on the Gane and Sarson shapes. Please show visuals

Deliverables:

The customer will send payment by mail and the payment will be posted through the system that updates the customer charge account.

The payments have to be deposited systematically to the bank, and recorded in the general ledger by the system, and the system should automatically send the customer a receipt.

$-$ The DFD should have two external entities, two data stores, and three processes.

$-$ Then create a weighted average selection table in Excel to select the best proposal based on this weighted average approach.

$-$ Then highlight the column with the best proposal in yellow.

$-$ Then create four to seven sentences as to why this vendor would be the best choice.

The information about the vendor choices are as follows:

There are three possible solutions from three different vendors. This project has two constraints$$cost and schedule. Management has determined that a cost of $$15,000$ or less would be good but up to $$20,000$ is acceptable. Management also has determined that a completion time of $180$ days or less would be good but up to $240$ days would be acceptable. The business user team has determined that there are five business requirements that they would like to see with the final product.

The firm utilizes a numbering system between $1$ and $5$ to determine if the vendor's proposal satisfies the constraints and requirements. For constraints, the firm usually rates proposals that meet the good criteria with the number $5,$ proposals that meet acceptable with the number $3,$ and those that do not meet the criteria limits would be rated with the number of $1.$ Regarding requirements, if the proposal fully satisfies the requirement, then it would be rated with the number $5.$ If the proposal satisfies at least $60\%$ of the requirement, then it would be rated with the number $3.$ All other proposals that do not satisfy at least $60\%$ of the requirement would be rated with the number $1.$

Furthermore, the importance of the constraints and requirements based on a $100\%$ scale are as follows.

Cost Constraint is $20\%.$

Schedule is $10\%.$

Requirement $1$ is $20\%.$

Requirements $2$ and $3$ are $15\%$ each.

Requirements $4$ and $5$ are $10\%$ each.

Project Proposals

Vendor A

Vendor B

Vendor C

Constraint Cost

$$20,750\mathrm{.}00$

$$19,500\mathrm{.}00$

$$14,950\mathrm{.}00$

Schedule

$160$ days

$200$ days

$250$ days

Requirement $1$

Fully Meets

Fully Meets

$75\%$ Meets

Requirement $2$

$75\%$ Meets

$50\%$ Meets

Fully Meets

Requirement $3$

Fully Meets

Fully Meets

Fully Meets

Requirement $4$

Fully Meets

Fully Meets

$50\%$ Meets

Requirement $5$

$75\%$ Meets

$75\%$ Meets

$75\%$ Meets