Answer:
The supplier should ship 2 days using B as it yields the lowest cost.
Explanation:
Base on the scenario been described in the question, we can use the following method to solve the question
Units	410 
Unit price	$ 156.00 
total cost of product to be shipped = (Unit price * Units) = 410*156	$ 63,960.00 
Holding cost = 39% ,39%*63960	$ 24,944.400 
Holding cost for 1 day = 24944.40/365	$ 68.341 
Shipper A	
Alternative	Shippping cost	Holding days	Holding days * Holding cost for 1 day	Total cost = Shipping + holding cost
2-Day	$ 538.00	2	$ 136.682	$ 674.68
3 day	$ 472.00	3	$ 205.022	$ 677.02
9 day	$ 406.00	9	$ 615.067	$ 1,021.07
Shipper b	
Alternative	Shippping cost	Holding days	Holding days * Holding cost for 1 day	Total cost = Shipping + holding cost
2-Day	$ 529.00	2	$ 136.682	$ 665.68
4 day	$ 455.00	4	$  273.363	$ 728.36
7 Day	$ 428.00	7	$ 478.386	$