Answer:
d. the atomic number remains the same.
Explanation:
First at all it's important to know how to read nuclear information

X is the atomic symbol, A the mass number and Z the atomic number of the element.
Gamma rays emitted on gamma decay are characterized as 
If we write the nuclear equation for the decay, we have that:

The sum of the mass numbers and atomic numbers on the right side has to be equal to the left side numbers of the equation, that means the mass number and the atomic number remains the same for the resulting atom to preserve the equality.
Mrnmrnamrnamrnamrnamrnamrnamrnamrnamrnamrna
Answer:
12.5J
Explanation:
Given parameters:
Mass of bucket = 1.7kg
Height = 75cm = 0.75m
Unknown;
Work done on the bucket by the person = ?
Solution:
To solve this problem, we use the work done equation;
Work done = force x distance = mgh
m is the mass
g is the acceleration due to gravity
h is the height
Now, insert parameters and solve ;
Work done = 1.7 x 9.8 x 0.75 = 12.5J
My answer is "Watt per square meter".