The effect of acid rain upon the yield of crops is of concern in many places. In order to determine baseline yields, a sample of 13 fields was selected, and the yield of barley (g/400m2) was determined. The output from SAS appears below:

QUANTILES(DEF=4) EXTREMES

N 13 SUM WGTS 13 100% MAX 392 99% 392 LOW HIGH

MEAN 220.231 SUM 2863 75% Q3 234 95% 392 161 225

STD DEV 58.5721 VAR 3430.69 50% MED 221 90% 330 168 232

SKEW 2.21591 KURT 6.61979 25% Q1 174 10% 163 169 236

USS 671689 CSS 41168.3 0% MIN 161 5% 161 179 239

CV 26.5958 STD MEAN 16.245 1% 161 205 392

A 95% confidence interval for the mean yield is:

a.220.2 ± 1.96(58.6)

b.220.2 ± 1.96(16.2)

c.220.2 ± 2.18(58.6)

d.220.2 ± 2.18(16.2)

220.2 ± 2.16(16.2)

Submarines control how much they float or sink in the ocean by changing the volume of air and water contained in large ballast tanks. when the tanks are completely full of water, the submarine increases its overall mass and sinks down to the bottom. when the tanks are completely full of air, the submarine reduces its overall mass and floats to the surface. depending on the density of the seawater surrounding the submarine, it will pump seawater in or out of the tanks in order to achieve the same overall density as the sea water and float neutrally in the water. the volume of the submarine never changes. when the tanks are completely full of water, a submarine with a volume of 7.8\times10^3\text{ m}^37.8×10 3 m 3 7, point, 8, times, 10, start superscript, 3, end superscript, space, m, start superscript, 3, end superscript has a total mass of 8\times10^6\text{ kg}8×10 6 kg8, times, 10, start superscript, 6, end superscript, space, k, g. the density of the seawater is 10^3\text{ kg/m}^310 3 kg/m 3 10, start superscript, 3, end superscript, space, k, g, slash, m, start superscript, 3, end superscript. to make that submarine float neutrally, and neither float nor sink in the ocean, what volume of water does that submarine need to subtract from its tanks?