Which of these statements explains why the ratio of adenine to thymine is nearly 1: 1 a adenine bases contains a form of thymine b adenine and thymine are identical in chemical composition c adenine and thymine pair with each other d adenine binds with phosphates, while thymine binds with nitrates

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

here's your answer.

the tricuspid valve is present between right atrium and right ventricle