Keeping in mind that an hour is 60 minutes.
Answer:
With a scientific calculator
Answer:

Step-by-step explanation:
Since the foci are at(0,±c) = (0,±63) and vertices (0,±a) = (0,±91), the major axis is the y- axis. So, we have the equation in the form (with center at the origin)
.
We find the co-vertices b from b = ±√(a² - c²) where a = 91 and c = 63
b = ±√(a² - c²)
= ±√(91² - 63²)
= ±√(8281 - 3969)
= ±√4312
= ±14√22
So the equation is

600000+80000+10=680,010 six hundred eighty thousand ten
Answer:
The volume is about 4.24 cm^3.
Step-by-step explanation:
From the question we are told that:
Diameter
Radius 
Height risen
Generally the equation for Volume of a Key is mathematically given by
Since Volume of a cylinder is Given as

Therefore


Correct Option A
The volume is about 4.24 cm^3.