antId = upper(antId);

switch antId
case 'TXAU'
% NGS CORS antenna. Type: TRM57971.00. Source of coordinates:
% http://www.ngs.noaa.gov/cgi-cors/corsage.prl?site=TXAU
rEcef = [-743774.390; -5460644.512; 3200347.710];
vEcef = [-0.0120; -0.0003; -0.0031];
epochYear = 2005.0;
case 'SAM2'
% NGS CORS antenna. Type: TRM57971.00. Source of coordinates:
% http://www.ngs.noaa.gov/cgi-cors/corsage.prl?site=SAM2
rEcef = [-751970.424; -5463638.752; 3193399.042];
vEcef = [-0.0123; -0.0003; -0.0033];
epochYear = 2005.0;
case 'TXTA'
% NGS CORS antenna. Type: TRM57971.00. Source of coordinates:
% http://www.ngs.noaa.gov/cgi-cors/corsage.prl?site=TXTA
rEcef = [-712254.169; -5450502.920; 3224462.604];
vEcef = [-0.0114; -0.0024; -0.0027];
epochYear = 2005.0;
case 'WRW0'
% WRW primary antenna. Type: TRM57971.00. Source of coordinates: L1-only CDGPS
% solution on the WRW0-TXAU baseline using the above TXAU coordinates.
% Velocity copied from TXAU velocity.
rEcef = [-741990.378; -5462227.718; 3198019.532];
vEcef = [-0.0120; -0.0003; -0.0031];
epochYear = 2005.0;
case 'WRW1'
error('Not yet defined');
case 'AUT0'
% CSR primary antenna. Type: TRM57971.00. Source of coordinates: Integrated
% MGEX network solution.
rEcef = [-741133.4180; -5456322.9775; 3208395.3863];
vEcef = [-0.0120; -0.0003; -0.0031];
epochYear = 2005.0

(30 pts) A single component substance is governed by the following...