You are on a Mariner class cargo vessel....

Question 1 of 2707066636eec28f7522a1c51c6ce

You are on a Mariner class cargo vessel. Your drafts are: FWD 17'-04", AFT 19'-04". You wish to increase the calculated GM of 3.0' to 4.2'. What tanks should you ballast? (Use the white pages in the Stability Data Reference Book.)

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Question 1 of 27070

🔍 Key Concepts

• Effect of adding ballast low in the ship on GM (metacentric height) • How KB, KG, and BM change when you add weight in specific double bottom or deep tanks • Using the Stability Data Reference Book white pages to find the moment changes for each tank or tank group

💭 Think About

• Which tanks in the options are located lowest in the ship and will therefore have the greatest effect on lowering KG and increasing GM? • Compare the combined effect of the listed tanks in each choice on GM: which combination gives you an increase close to the 1.2 feet you need (from 3.0' to 4.2') according to the tables? • Are any of the listed tanks located farther forward or aft in a way that could cause an undesired trim change, even if they improve GM?

✅ Before You Answer

• From the white pages, check the GM change per ton (or per full tank) for each of the candidate tanks: DB2, DB3, DB4, DB6, DT7, DT8. • Verify which tanks are double bottoms (DB) versus deep tanks (DT) and their vertical positions relative to the keel. • Sum the GM contributions from all tanks in each answer choice and confirm which combination gets you closest to GM = 4.2' without overshooting too much.