Why can even functions have constant value in their equations, while odd functions cannot?

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).

When 142 is added to a number the result is 64 more times the number my options are 35 37 39 41

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document