1.In choosing a new machine, your boss wants you to be as cost-efficient as possible, but she also wants the best efficiency. Consider the following options. Which is your best option?
Option 1: This $5,000 machine is supplied energy at a rate of 1,900 W and does useful work at a rate of 1,786 W.
Option 2: This $4,500 machine is supplied energy at a rate of 1,450 W and does useful work at a rate of 1,300 W.
Option 3: This $4,750 machine is supplied energy at a rate of 1950 W and does useful work at a rate of 1833 W.
Option 4: This $4,750 machine is supplied energy at a rate of 2,000 W and does useful work at a rate of 1,822 W.
O A. Option 1
OB Option 3
C. Option 4
D. Option 2

This $4,750 machine is supplied energy at a rate of 1950 W and does useful work at a rate of 1833 W. OPTION 3.

Explanation:

it has the highest power output

b would be the answer

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.