A negative to a negative charge will make a neutral charge.
The horizontal change between two points on a graph is called the 'run'.
The vertical change between two points is called the 'rise'.
Answer:
A ruby is measures a 9 on the Mohs Scale of Hardness, second only to diamond and matched with sapphire. This makes a ruby an extremely hard and durable gemstone.
A sapphire is the birthstone for September. It is also a traditional gift for those celebrating 5th or 45th anniversaries.
Answer:
reflection is the act of reflecting or the state of being reflected while echo is
reflection of sound waves from a surface back to the initial listener
