Answer:
transform boundary
Step-by-step explanation:
I'm not too sure, but a transform boundary is where two plates crash into each other, creating mountains.
Answer:

Step-by-step explanation:

Answer:
b
Step-by-step explanation:
Answer:
18
Step-by-step explanation:
Answer:
1st option: when a sperm joins an egg
Step-by-step explanation:
A sperm will be accepted into the egg, and fertalize it