Feeder Computer Systems Design Ltd. (Feeder) designs and installs com puter networks for commercial customers. In December 2016, Feeder signed a contract with Magyar Telecommunications Ltd. (Magyar) to design and install a new network for Magyar's production centre in Winnipeg. Magyar's year-end is December 31. The following events pertain to the contract with Magyar:
i. December 13, 2016: The contract between Feeder and Magyar is signed. Magyar will pay $750,000 for the system and the system will cost Feeder $450,000 to design, produce, and install. The contract provides an 18-month warranty to make any re pairs or adjustments required. Magyar will pay within 90 days of completion of the installation of the system.
ii. October 15, 2017: Installation of the system is completed.
iii. December 12, 2017: Warranty work costing $22,500 is performed.
iv. January 8, 2018: Feeder receives payment in full from Magyar.
v. April 15, 2018: Warranty expires.

Required:
Prepare the journal entries required for the above events assuming the following:
a. Revenue is recognized when the contract is signed.
b. Revenue is recognized when installation of the system is complete.
c. Revenue is recognized when cash is collected.
d. Revenue is recognized when the warranty period expires.