Aisha wonders whether wind or water causes the most erosion. She set up an experiment in which she used a watering can to pour water down a pile of dirt. She then used a fan to blow wind on a second pile of dirt that is the exact same shape and size as the first pile of dirt. Aisha then measured how the height of the dirt piles changed. She also drew pictures of how their shape changed. In this experiment, what was the outcome variable (dependent variable)? A.
the height and shape of the dirt piles
B.
the tools used to measure the dirt piles
C.
the agent of erosion applied to the dirt piles
D.
the time the dirt piles were eroded away

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.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).