Sidney throws a basketball into a pool of water. the ball lands 10 feet from the edge of the pool, and the waves from the ball's impact reach the edge in 5.0 seconds. later on, sidney bounces a basketball on the floor of her school gym. if ian is sitting on the floor 10 feet away from where sidney bounces the ball, the waves traveling along the floor from the ball's impact will

The answer would be that

"reach him in less than 5.0 seconds."

This is because waves travel through different materials at different speeds.

Generally, more solid or rigid materials will transmit vibrational waves faster than softer or more fluid materials.  

Even though the waves traveling through the gym's floor are probably too small to see, they will travel much faster than similar waves in a pool of water.  

This is why Ian will feel the bouncing ball on the floor in less than 5.0 seconds.

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.