Explanation:
The discovery of the new elements, and the new data on neutron capture, was kept secret on the orders of the U.S. Military until 1955 due to Cold War tensions. Later the Berkeley team was able to prepare elements 99 and 100 in the lab by neutron bombardment of Pu-239 in a cyclotron.
Answer:
C) Her central idea is too vague and does not restrain the number of main points.
Explanation:
The statement "Dog care is very difficult" is very vague, because it is using an adjective that is very general, and can be interpreted or comprehended in many different ways.
Allison should instead try to narrow down her central idea. She could say that "Dog care is very difficult because of _______", or she could also use a more specific adjective accompanied by a supporting phrase like "Dog care is very expensive, costs are soaring"