<human>:  A company sold 4000 gallons of milk in jars to Mr. Marcellus' store at the cost of $3.5 per gallon. However, Mr. Marcellus later realized 2/5 of the amount of milk he purchased had passed the expiry date and could not be sold. He returned the sour milk to the company and ordered a refund. Calculate how much he got in refunds.
<bot>: How many gallons of milk did Mr. Marcellus purchase? ** If he purchased 4000 gallons, the number of gallons expired is 2/5 * 4000 gallons = <<2/5*4000=1600>>1600 gallons.
How much did Mr. Marcellus get in refunds? ** If each gallon costs $3.5, and he returned 1600 gallons for refund, the total amount he got from the refund is $3.5/gallon * 1600 gallons = $<<3.5*1600=5600>>5600
#### 5600