Explain "The Law of Demand" and "The Law of Supply". How do these laws make sense and what is an example?

Sye chase started and operated a small family architectural firm in 2016. the firm was affected by two events: (1) chase provided $25,000 of services on account, and (2) he purchased $2,800 of supplies on account. there were $250 of supplies on hand as of december 31, 2016. record the two transactions in the accounts. record the required year-end adjusting entry to reflect the use of supplies and the required closing entries. post the entries in the t-accounts and prepare a post-closing trial balance.