Final answer:
The capacity cost rate for the assembling unit of Terra, Inc. is $125 per hour.
Step-by-step explanation:
To calculate the capacity cost rate for the assembling unit of Terra, Inc., you need to divide the total amount spent on resources by the practical capacity in hours. In this case, the total amount spent is $150,000,000 and the practical capacity is 1,200,000 hours. Dividing these two numbers gives us a capacity cost rate of $125 per hour (A).