2. When volcanoes erupt, they emit large plumes of hot smoke and ash, which can spread and cover miles of sky. Which process lifts the hot, black clouds into the sky?
A. Radiation that causes thermal energy to transfer into the clouds and hold them
together
B. Conduction that causes thermal energy to pass from the smoke into the ground
C. Conduction that causes warmer air to spread and cooler air to condense into clouds
D. Convection that causes warmer air to rise and cooler air to sink into its place

i would say b

explanation:

but i think i would need more information than that

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.