PLEASE HELP
Simplify the expression to a + bi form:
√ 25- √ -25 – √ 36 – √ -4

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?

Atransformation t : (x, y) (x-5,y +3) the image of a(2,-1) is