Final answer:
The leaf blower from Lang Manufacturing Co. appears to be in the maturity stage of the product life cycle, indicated by steady sales and profit growth over four years but signs of plateauing in the most recent data.
Step-by-step explanation:
Considering the data provided by the management accountant at Lang Manufacturing Co., we can analyze the stage of the sales life cycle that the product, a leaf blower, is in. The information shows annual sales have a positive average annual change over the last four years but a smaller rise over the last year, indicating the product is still growing but at a slower rate. The unit sales price has been increasing steadily, which could be due to inflation or increased value perception among customers. Notably, although the total profit has grown significantly over a four-year average, there is a slight decline in the most recent year, which might suggest that the product is starting to face challenges such as market saturation or increased competition contributing to rising costs. At this stage, it seems the leaf blower may be transitioning from the growth stage to the maturity stage where the sales growth starts to plateau.