The following data are for Guava Company's retiree health care plan for the current calendar year.

Number of employees covered	5
Years employed as of January 1	4 (each)
Attribution period	20 years
EPBO, January 1	$61,000
EPBO, December 31	$67,100
Interest rate	10%
Funding and plan assets	None

What is the interest cost to be included in the current year's postretirement benefit expense?

a)$1,100.

b)$1,342.

c)$6,100.

d)$1,220.