The tens digit of a number is twice the ones digit. the sum of the digits in the number is 12. what is the number?

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.

Free points also plz look my profile and answer really stuff

The ivring berlin learning center would like a possible net profit of $650,000 on its new resource manual it sells to schools. the fixed costs for producing the manual are $780,000 and the variable cost per package is $19.85. if the estimated unit sales are 1,250,000 units, what selling price unit should the ivring berlin learning center try?