(this one is just for fun) a number is divisible by 3 if the sum of its digits is divisible by 3 a number is divisible by 6 is the sum of its digits is divisible by 3, and the number is even. a number is divisible by 9 if the sum of its digits is divisible by 9. a number is divisible by 11 if the alternating sum of its digits is divisible by a multiple of 11 (so divisible by 0, 11, 22, 33, etc - don't forget the zero, that is also a multiple of 11). for example, the number 2354 is divisible by 11 since 2-3+5-4=0. the number 9680 is divisible by 11 since 9-6+8-0=11 c given that information for what values of a and b is the number 12ab divisible by 99?

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.

scientific laws are the result of testing theories and proving them to be facts.

it has to be b, about 97 percent.