Answer:
The correct answer is "0.32 mL".
Explanation:
The given values are:
Density of gold bar,
d = 19.3 g/mL
Mass of gold bar,
m = 6.3 grams
Now,
The volume will be:
⇒ 
or,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
The last one, 12p 12e 12n
Here we can say that by energy conservation principle
Elastic potential energy of spring will convert into kinetic energy of the block
so here we will have

we also know that
k = 360 N/m
x = 11 cm
m = 1.85 kg
now we will use all in above equation




so it will move with speed 2.17 m/s after separating from spring
The only one on the list that I know is radioactive is Carbon-14.