Table:
text: 1982 IMSA GT Championship season
Schedule
Schedule
Race Length_ Class_ Circuit Date_
24 Hour Pepsi Challenge 24 hours All Daytona International Speedway January 30 January 31
Coca-Cola 12 Hours of Sebring 12 hours All Sebring International Raceway March 20
Road Atlanta Grand Prix miles (km) GTP/GTO Road Atlanta April 4
Road Atlanta Grand Prix 45 minutes GTU Road Atlanta April 4
Los Angeles Times / Toyota Grand Prix 6 hours All Riverside International Raceway April 25
Datsun Monterey Triple Crown 45 minutes GTU Laguna Seca Raceway May 2
Datsun Monterey Triple Crown miles (km) GTP/GTO Laguna Seca Raceway May 2
Charlotte Camel GT 500 500km All Charlotte Motor Speedway May 16

text: 1982 IMSA GT Championship season
Schedule
Schedule
Race Length_ Class_ Circuit Date_
G.I. Joe`s / Toyota Grand Prix miles (km) GTP/GTO Portland International Raceway August 1
G.I. Joe`s / Toyota Grand Prix 30 minutes GTU Portland International Raceway August 1
Labatt`s 50 GT 6 hours All Mosport Park August 15
Pabst 500 miles (km) All Road America August 22
Lumbermen`s Six Hours 6 hours All Mid-Ohio Sports Car Course September 5
Sprite 500 500km All Road Atlanta September 12
Grand Prix of Pocono miles (km) All Pocono Raceway September 26
Daytona Three Hour 3 hours All Daytona International Speedway November 28

text: 1982 IMSA GT Championship season
Schedule
Schedule
Race Length_ Class_ Circuit Date_
Red Roof Inns Sprints 1 hour GTU Mid-Ohio Sports Car Course May 23
Red Roof Inns Sprints miles (km) GTP/GTO Mid-Ohio Sports Car Course May 23
Coca-Cola 400 1 hour GTP/GTO Lime Rock Park May 31
Coca-Cola 400 45 minutes GTU Lime Rock Park May 31
The NTW 300 miles (km) GTU Summit Point Motorsports Park June 20
Paul Revere 250 miles (km) All Daytona International Speedway July 3
Pepsi Grand Prix 200km All Brainerd International Raceway July 11
California Grand Prix miles (km) GTP/GTO Sears Point Raceway July 25
California Grand Prix miles (km) GTU Sears Point Raceway July 25

Question: What is the length of the Laguna Seca Raceway circuit with a GTU class for the 1982 IMSA GT Championship season?