How are indifference curves and isoquant curves similar, and how do they differ?

How are budget lines and isocost lines similar, and how do they differ?

Explain the relationship between the marginal cost curve, and the average total cost and average variable cost curves. Why do, all these curves have the shape they do?

Explain the relationship between average product of labor and marginal product of labor, and how it relates to the production stage of a firm.

What is the difference among increasing returns to scale in production, economies of scale in costs, and economies of scope?