Edmund Kells constructed his own x-ray machine.
A calorie is a unit that is used to measure energy.
The verb here is "had given"; this is past perfect: it's a perfect tense, because it has a past participle with the -ed ending ("given") and it's the past perfect because the auxiliary verb is the past form of "have": had.
B
Explanation:
because you can answer the question. "what was he surprised at?" at the ease
