Water (liquid)
Pressure (atm)
1
05-
025-
Ice
( (solid)
Water vapor
(gas)
10
101
100
Temperature (°C)
What do the sections between the lines on a phase diagram represent?
A. The regions in which temperature and pressure change a
substance's phase
B. The conditions in which a substance exists in a certain phase
C. The ranges where temperature and pressure are constant in a
substance
D. The areas in which the kinetic energy of a substance is constant

distance, luminosity, brightness, radius, chemical composition, and temperature

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.