Bouden Company performed the following activities during 2016:
a. Built an oil shale plant to test the feasibility of large-scale exploitation
b. Tested a new type of machine to evaluate its potential usefulness in production
c. Modified a machine to make it suitable for tilling; a customer’s order
d. Designed a new plant to produce the same products more efficiently
e. Tested alternative production methods in an attempt to increase efficiency
Which of the activities are considered R&D? Justify' your reasons for each answer.