When a river flows into a standing body of water, what forms? ...

[Chelseaamend]

When a river flows into a standing body of water, what forms?
 A)natural levees
 B)deltas
 C)scarps
 D)alluvial plains
 E)underwater canyons

Question 2

Melting of Earth's crust yields mostly silica-rich magmas because ____.
 A)the most abundant minerals in Earth's crust are silicates
 B)silica is more easily melted than other minerals
 C)many minerals produce silica when melted
 D)silica has extremely low viscosity and move quickly up to Earth's crust from far underground
 E)when silicon reacts with sodium chloride it form silica

[carojassy25]

Answer to Question 1

B

Answer to Question 2

A