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Y NOTES The weekly revenue from the sale of rubies at Royal Ruby Retailers (RRR) is increasing at a rate of $30 per $1 increase in price, and the price is decreasing at a rate of $0.50 per additional ruby sold. You are given that , and dp dp da What is the marginal revenue? HINT [See Example 5.] 4 State the units of measurement. O additional rubies sold per weekly revenue O dollars per additional ruby sold O additional rubies sold per dollar O weekly revenue per additional ruby sold Interpret the result. The revenue is -Select-- y at a rate of $ per additional ruby sold