This is defined as a sudden, intense variation in brightness that occurs when magnetic energy that has built up in the solar atmosphere is suddenly released. Radiation is emitted across the entire electromagnetic spectrum.
This is a
A)
coronna
B)
sunspot.
C)
photoflare.
D)
solar flare.

you need to stop taking that class

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.

hypostyle hall;