Please help prepare journal entries for this. Thank you.

And also explain why for each for better understanding.

The following information pertains to Lucas Solar Panels July 1 Sold 150,000 of solar panels to Harrison Limited with terms 2/15,n/30. Lucas uses the gross method to record cash discounts. Lucas estimates allowances of 1,500 will be honored on this sale. 12 Sold 87,000 of solar panels to Fisher Associates with terms of 3/10, n/60. Lucas expects no allowances related to this sale. 18 Fisher paid Lucas for its July 12 purchase. 20 Harrison calls to indicate that the panels purchased on July 1 work well, but the color is not quite right. Lucas grants a credit of 2,000 as compensation. 29 Harrison paid Lucas for its July 1 purchase. 31 Lucas expects allowances of 4,500 to be granted in the future related to solar panel sales in July. Prepare the necessary journal entries for Lucas. (Credit account titles are automatically indented when the amount is entered. Do not indent manually. Record journal entries in the order presented in the problem. If no entry is required, select "No Entry" for the account titles and enter 0 for the amounts.)