By The Associated PressThe price of copper surged 7 percent Friday after the government reported a sharp pickup in hiring over the past three months. Copper for July delivery jumped 21 cents to $3.3145 a pound Friday. It was the biggest one-day jump since Oct. 24, 2011. The price of copper tends to rise when investors expect the economy to strengthen. Copper has a wide range of industrial uses in making electronics and construction materials, and demand for the metal increases when manufacturing and homebuilding accelerate. The Labor Department reported that employers added 165,000 jobs last month, and far more in February and March than first thought. The unemployment rate fell to a four-year low of 7.5 percent, an encouraging signal to investors that the job market is improving. The price of crude oil also rose following the jobs report. Demand for oil also tends to increase when the economy picks up, as factories produce more, people drive more and businesses use more fuel to ship goods. Crude oil rose $1.62 to $95.61 a barrel. In other energy futures trading on the New York Mercantile Exchange, wholesale gasoline rose 4.48 cents to finish at $2.8254 a gallon. Heating oil rose 2.89 cents to end at $2.8844 a gallon and natural gas rose 1.6 cents to finish at $4.0410 per 1,000 cubic feet. In other metals trading, gold for June delivery edged down $3.40 to $1,464.20 an ounce, or 0.2 percent. Silver for July delivery rose 18.4 cents to $24.014 an ounce, a gain of 0.8 percent. July platinum rose $1 to $1,501.20 an ounce, or 0.1 percent. June palladium was unchanged at $693.30 an ounce. Crop futures ended mixed. July wheat fell 7.5 cents to $7.21 a bushel, July corn fell 0.75 cent to $6.6125 a bushel and July soybeans rose 15 cents to $13.8725 a bushel.