An executive invests $21,000, some at 8% and the rest at 7% annual interest. If he receives an annual return of $1,570, how much is invested at each rate?

One expression below in undefined, and the other expression has a well defined value. which expression is undefined and explain why it has no value. which expression is defined? what is the value of that expression and how do you know? what is a different expression using a trig inverse function that is also undefined?

Write the equations in logarithmic form 10^3=1,000

When 60% of a number is added to the number the result is 192 what is the bumber