Answer:
0.25miles/min
Explanation:
Instantaneous speed of a person or an object is its speed at a particular moment usually at a period of time.
The speedometer of a car reports the instantaneous speed.
It can be mathematically expressed as;
Instantaneous speed = 
At 20min the distance covered is 5miles;
Instantaneous speed = 
= 0.25miles/min
CORRECT ANSWER:
d. Anywhere from days to thousands of years.
STEP-BY-STEP EXPLANATION:
The whole question from book is
How long do molecules of groundwater stay in the
ground?
a. Days
b. Weeks
c. Months
d. Anywhere from days to thousands of years
Answer:
Reflected ray. A ray of light or other form of radiant energy which is thrown back from a nonpermeable or nonabsorbing surface; the ray which strikes the surface before reflection is the incident ray.
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.
