oops pls forgive me I accidentally did the wrong question.
A volcano is formed when magma (Lava) spews up from deep within the earth. After each eruption the Volcano gets bigger and bigger, so basically after periods of time the volcano will get larger. Lava will rise in cracks in the earth or weak spots in the earths crust. The pressure is relieved thus resulting in a volcanic eruptions it forms the new crust and then eventually builds up in that spot making a volcano. They also form in places called hot spots and various other places.
The half life of uranium- 238 is
4.46 x10^9 years
Explanation
Half life is the time taken for the radioactivity of a isotope to fall to half its original value.
The original mass of uranium-238 is 4.0 mg
Half of original mass of uranium = 4.0 mg /2 = 2.0 mg
since it take 4.46 x 10^ 9 years for the sample to half the half life of uranium -238 = 4.46 x10^9 years
In order to change celcius to kelvin always add 73 to it leaving you with -195.93
Because the proton has a mass of 1 and a neutron has a mass of 1, we know that there is exactly one proton in the nucleus (because of the atomic number) which therefore tells us there are no neutrons as adding one would make the mass more than one.