use excel please and explain as you go a bit

VOOM HAS FOUR WAREHOUSES 1, 2, 3, AND 4. VOOM NEEDS TO SUPPLY 100 TONS TO RETAILER P, 300 TONS TO RETAILER Q, AND 300 TONS TO RETAILER R. THE COST OF DELIVERY FROM EACH WAREHOUSE TO RETAILERS IS PROVIDED IN THE FOLLOWING TABLE. WHILE EACH OF THE WAREHOUSES HAS AN INVENTORY OF 400 TONS THEY CAN SUPPLY, R REQUIRES THAT EVERY WAREHOUSE SUPPLIES AT LEAST 25 TONS TO R. THERE IS A SPECIAL ARRANGEMENT BETWEEN WAREHOUSE 4 ANDR WHICH REQUIRES THAT WAREHOUSE 4 HAS TO SUPPLY EXACTLY 100 TONS TO R. ON THE OTHER HAND, P CANNOT TAKE MORE THAN 50 TONS EACH FROM WAREHOUSE 1 AND 2. USE LINEAR PROGRAMMING TO PROVIDE VOOM A PLAN THAT WILL KEEP THEIR TRANSPORTATION COST TO THE MINIMUM Delivery cost/ton ($) Warehouse 1 $ 14.00 $ 30.00 $ 20.00 Warehouse 2 $ 30.00 $ 40.00 $ 15.00 Warehouse 3 $ 18.00 $ 20.00 $ 14.00 Warehouse 4 $ 15.50 $ 12.00 $ 18.00