Answer:
c. find the slope of the velocity time graph
Probably for the umbilical cord that connects babies (from their early stages in the womb to their removal) to their mothers. The cord is cut, forming the belly button. This is analogous to astronauts in space.
Answer:
2.11eV
Explanation:
We know that speed of light is it's wavelength times frequency.

Planck's constant is 
The energy gap is calculated by multyplying the light's frequency by planck's constant:

Hence, the energy gap is 2.11eV