Who was febanachi and wht did he accomplish

The name he is commonly called, "Fibonacci" (Italian: [fiboˈnattʃi]), was made up in 1838 by the French historian Guillaume Libri and is short for "filius Bonacci" ("son of (the) Bonacci") and he is also known as Leonardo Bonacci, Leon  Fibonacci was an Italian mathematician from the Republic of Pisa, considered to be "the most talented Western mathematician of the Middle Ages". The name he is commonly called, "Fibonacci",ardo of Pisa, Leonardo Pisano Bigollo, or Leonardo Fibonacci.

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.

v 154.9= 0.9 length length s little over 154.9cm