Which of the listed flash points indicates a grade D combustible liquid?

A flash point is the lowest temperature at which vapors of a combustible liquid ignite when an ignition source is present. Understanding the classifications of liquids based on their flash points is crucial in the maritime industry, particularly when dealing with the handling and storage of various petroleum products.

Grade D combustible liquids are defined by a flash point that is less than 100°F (37.8°C). In this case, a flash point of 87°F falls within this classification, indicating that the liquid can readily form ignitable vapors at this relatively low temperature.

Using this information, it's clear that 87°F meets the criteria for a Grade D combustible liquid, as it is below the 100°F threshold. This classification is significant for safety measures on vessels and during transport, as it implies that extra precautions are necessary to avoid ignition sources in the vicinity of such liquids.

The other choices provided (160°F, 155°F, and 65°F) reflect flash points that do not align with the Grade D classification. For example, 160°F and 155°F both far exceed the limit for Grade D substances, indicating that those liquids belong to higher grades of flammable materials. Meanwhile, while 65°F is below 100°F and might seem plausible