What is the value of the expression 3b+20 for b=30

Agreeting card company can produce a box of cards for $7.50. if the initial investment by the company was $50,000, how many boxes of cards must be produced before the average cost per box falls to $10.50?

Which equation represents the function on the graph?

Which statement best explains why ben uses the width hi to create the arc at j from point k