hey i had practice questions i tried can you help me out with these

Q #1) (5 Marks) Using a Perpetual Inventory System, prepare journal entries for the following transactions. Ignore Excise Taxes. 1-Feb-20 Purchased $5,000 of Inventory; terms 1/10, n/30 4-Feb-20 Sale to customer for $12,000 (Cost of Goods $6,000); terms 2/10, 1/30 10-Feb-20 Paid for purchase from Feb 1, 2020 11-Feb-20 Some of the product sold on Feb 4th didn't match the customer's specifications. We agreed to accept the inventory back and reduced their account by $1,000. The inventory wasn't in good condition and wasn't returned to inventory (in other words, it was thrown out). 16-Feb-20 Customer from Feb 4, 2020 paid off their outstanding balance. Q #2) (2 Marks) Using the above transactions from Q#1, compute the Net Sales, Gross Profit Margin, and Gross Profit Margin Percentage (%) for the month of Feb, 2020. Q #3) (2 Marks) Assume GST is 5% and PST is 6%. Using a Perpetual Inventory System, prepare the following journal entries. 2-Feb-20 Purchased $10,000 of Inventory with cash 5-Feb-20 Sale to customer for $15,000 (Cost of Goods $6,000); terms 1/10, n/30