It’s
3496 you can google this you know
Answer: Helium (He) and Selenium (Se) both are non metals ends with ium sound
Explanation:
He is a inert gas and Se belongs to oxygen family (VI A group)
Answer:
The mass of gold in crown is 960.61 g.And the volume of gold is
.
Explanation:
Density is defined as mass of the substance present in unit volume of the substance.
Mass of gold in an alloy of crown= m
Mass of silver in an alloy of crown = M
Volume gold in an alloy of crown= v
Volume of silver in an alloy of crown = V
Density of gold = 
Density of silver = 
Volume of the crown = 

..(1)
Mass of eh crown = 1050 g
..(2)
Solving equation (1) and (2):
m = 960.61 g
M = 89.39 g
Volume of the gold = v = 
Volume of silver = V = 
The mass of gold in crown is 960.61 g.And the volume of gold is
.