16 what feature is labeled d in figure 10-1
a. pipe
b. volvanic neck
c. crater***

d. lava flow
17 what feature is labe; ed a in fingure 10-1
a. pipe***
b. volcanic neck
c. crater
d. vent

18 what type of volvano is illustrated in figure 10-1
a. volcanic neck
b. shield volcano
c. cinder cone
d. compostie cone***
the volcano goes with the questions so do report me. i just need and i will give you brainiest crown for two people to answer

16. The correct answer is option C, that is, crater.  

A circular depression around a volcanic vent is known as a volcano crater. This is the region from where the ash, lava, and rock erupts out of a volcano. In the majority of the conditions, the volcano crater is situated at the top of the volcano.  

17. The correct answer is option B, that is, volcanic neck.  

A lava neck or volcanic neck is also known as a volcano plug refers to a volcanic object produced when magma toughens inside a vent on an active volcano. A plug can result in an extreme creation of pressure if the elevating volatile-charged magma is trapped underneath it.  

18. The correct answer is option D, that is, composite cone.  

Composite cone volcanoes also are known as stratovolcanoes. These are the cone-shaped volcanoes comprising of the layers of ash, lava, and rock debris. These volcanoes are grand site and can grow to an elevation of 8000 feet or more.  

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.