Question

If mass is equal to 89.87, the speed of light is 3x10 to the 8 and energy is e=mc squared, what is energy?

Answer 1

Here's a good calculator for that e=mc^2 stuff
http://www.1728.org/einstein.htm
but I'll also work it out for you.

Answer 2

First of all you have to get the units right.
If we use mass of 89.87 grams and the speed of light is 29,979,245,800 centimeters per second (okay about 3 x 10^10 cm/sec) our answer will be in ergs

When we use mass in kilograms, and speed of light equals 3 x 10^8 meters/second then the answer is in joules.

Answer 3

If you are using speed of light in meters per second, (3 x 10^8 m/sec) then we'll assume the 89.87 mass is in kilograms.

E=mc^2

Energy (joules) = 89.87kg * (3 x 10^8 m/sec)^2

Energy = 89.87 * 9 x 10^16

Energy = 8.09 x 10^18 joules