The Helena Gage reads 9.4 feet. The high...

Question 1 / 2707066636eea28f7522a1c51b323

Question 1 of 2707066636eea28f7522a1c51b323

The Helena Gage reads 9.4 feet. The high point on your towboat is 46 feet above water. What is the vertical clearance when you pass under the Helena Highway Bridge?

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Question 1 of 27070

The Helena Gage reads 9.4 feet. The high point on your towboat is 46 feet above water. What is the vertical clearance when you pass under the Helena Highway Bridge?

🔍 Key Concepts

• Vertical clearance is the distance from the water surface to the lowest part of the bridge span • How river gage readings relate to a charted or reference clearance at a specific gage height • Whether you should add or subtract the boat’s air draft (46 feet) from the available clearance under the bridge

💭 Think About

• Think about what the gage reading is telling you: if the river is higher than the reference level, does that make the bridge clearance more or less? • If you know the distance from the water to the bridge, how do you use your towboat’s 46-foot height to determine if you can safely pass? • Which operation (addition or subtraction) correctly combines the gage-based bridge clearance with your vessel’s height to get the remaining vertical clearance above your highest point?

✅ Before You Answer

• Be clear on whether the question is asking for clearance under the bridge or clearance above your vessel as you pass • Confirm that you’re consistently using feet and that you only combine values that represent compatible distances (water-to-bridge vs boat height) • Double-check if you are using the gage reading in the same way it would be used in a bridge clearance table (does an increasing gage reading increase or decrease clearance?)

Question 1 of 27070

The Helena Gage reads 9.4 feet. The high point on your towboat is 46 feet above water. What is the vertical clearance when you pass under the Helena Highway Bridge?

56.0 feet

64.2 feet

106.1 feet

79.5 feet

Question 1 / 2707066636eea28f7522a1c51b323

Question 1 of 2707066636eea28f7522a1c51b323

The Helena Gage reads 9.4 feet. The high point on your towboat is 46 feet above water. What is the vertical clearance when you pass under the Helena Highway Bridge?

Back

Question 1 of 27070

The Helena Gage reads 9.4 feet. The high point on your towboat is 46 feet above water. What is the vertical clearance when you pass under the Helena Highway Bridge?