Activation Energy is the amount of energy needed to get a reaction started.
The
sun is a ball of hot gases containing different kinds of elements at different
cores. It has a very high temperature that radiates all throughout the Milky
Way galaxy. The sun has three main parts; photosphere, chromospheres
and corona. The outer core of a star located at the chromospheres contains
mostly of hydrogen. Inside the hydrogen is helium then carbon, oxygen, neon,
magnesium silicon and the inert gas. The photosphere is scattered by the loose electrons in the corona’s plasma.
Answer:
(a) 0 (b) 
Explanation:
Given that,
Mass of a supertanker, 
The engine of a generate a forward thrust of, 
(a) As the supertanker is moving with a constant velocity. We need to find the magnitude of the resistive force exerted on the tanker by the water. It is given by :
F = ma, a is the acceleration
For constant velocity, a = 0
So, F = 0
(b) The magnitude of the upward buoyant force exerted on the tanker by the water is equal to the weight of the ship.
F = mg

Hence, this is the required solution.
Answer:
After a nucleus with 85 protons undergoes alpha decay, it has 83 protons.
Explanation:
In an alpha particle there are two protons
In the given substance's nucleus, there are total of 85 protons
After the decay, the proton number reduce
The current proton number after decay is
85 -2 = 83
After a nucleus with 85 protons undergoes alpha decay, it has 83 protons.
Answer:
In my opinion I think it's B I'm so sorry if I get this wrong