Multiply (4.3•10^5) (2•10^8) Then write it in scientific notation

Acollege is planning to construct a rectangular parking lot on land bordered on one side by a highway. the plan is to use 680 feet of fencing to fence off the other three sides. what dimensions should the lot have if the enclosed area is to be a maximum?

Luke wants to reduce the area of his rectangular garden by 1/4 the expression 14/w can be used to represent this change. what is another way to write this expression?

Brad earns $12.75/hr and works 40 hours a week. what is his gross annual income?