TRW, Inc., is a global company that specializes in producing automotive, spacecraft, and information system products. The following (partial) segment data was reported (dollars in millions):

December 31 1994 1993 Sales:

Automotive $5,679 $4,538 Space and defense 2,812 2,792 Information systems 596 618 Operating profit:

Automotive $476 $309 Space and defense 175 199 Information systems 96 74 Identifiable assets:

Automotive $3,481 $3,004 Space and defense 1,111 1,253 Information systems 622 752 Required

a. Calculate the return on assets of 1994 for each segment (use operating profit and ignore interest expense).

b. Calculate each segment’s operating income as a percentage of sales.

c. Why is the segment-by-segment information important for an investor to have? Which ratio results will be most important to investors? Why?