What makes plants the beginning of the food chain

What would be the strength of earth's gravitational field at a point where an 80.0 kg astronaut would experience a 80% reduction in weight

If the work required to stretch a spring 3 ft beyond its natural length is 15 ft-lb, how much work is needed to stretch it 27 in. beyond its natural length?

In the nineteenth century, gregor mendel first determined some basic rules of genetics that have been observed throughout all types of life. no observations have disproved these basic rules of genetics. charles darwin developed the idea of biological evolution around the same time, but he was unaware of mendel’s discoveries in genetics. over a century later, darwin’s idea of evolution was modified in order to incorporate mendel’s rules of genetics along with the other evidence that darwin had used. what is most likely the relationship between mendel’s rules of genetics and darwin’s idea of biological evolution? a.)mendel’s genetics states laws that are now part of the theory of biological evolution.b.)biological evolution states laws that are part of mendel’s theory of genetics.c.)mendel’s genetics replaced darwin’s entire concept of biological evolution.d.)biological evolution is a law that explains why all genetics exist.