I really need help with Geometry. I attached 2 of the problems to see if anyone knows it, before I post more questions. Thank you!!!

What is the image of c for a 90° counterclockwise rotation about a? (3, 7) (-1, 3) (7, 3)

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?

Arectangle has a length of 6cm by 8cm what is the length of a diagonal of the rectangle