Answer: D. movement of material along a coast by waves that approach at an angle to the shore.
Explanation:
Longshore drift is also referred to as the littoral druft and it means the sediment that is moved by the longshore current.
Longshore drift is the movement of material along a coast by waves which approach at an angle to the shore but then recede down the beach.
Therefore, the correct option is D.
Let volume of empty boat be = 100% = 1V
and mass of boat be M
In water 10%, 0.1V of the volume is submerged.
Mass, m of 1200kg increases the submerging from 10%, 0.1V to 70%, 0.7V
M leads to 0.1V boat submerging
boat submerging.
M + 1200kg leads to 0.7V boat submerging.
This is 60%, 0.6 V increase
By comparison
(M+1200kg) * 0.1V = 0.7V * M
0.1M + 120kg = 0.7M
120kg = 0.7M - 0.1M
120kg = 0.6M
M = (120/0.6)kg
M = 200kg.
The mass of the boat is 200kg.
Explanation:
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