Computer memory. The capacity (bits) of the largest DRAM (dynamic random access memory) chips commonly available at retail has increased as follows:17 DATADATA DATADATADATA DATADATADATADATADATA DATADATADATADATADATA DATADATADATADATADATA DATADATADATADATADATA DATADATADATADATADATA DATADATADATADATADATA DATADATADATA DATADATADATADATADATA DATA FILE DRAM Year Bits Year Bits 1971 1,024 1993 16,384,000 1980 64,000 1999 256,000,000 1987 1,024,000 2000 512,000,000

(a) Make a scatterplot of the data. Growth is much faster than linear.

(b) Plot the logarithm of DRAM capacity against year. These points are close to a straight line.

(c) Regress the logarithm of DRAM capacity on year. Give a 90% confidence interval for the slope of the population regression line.