C) The Earth is at least three billion years old. :)
Answer AND Explanation:
Bone tissue consists of an organic matrix which is impregnated with calcium salts especially phosphates and carbonates. The organic matrix confers toughness to bone while calcium salts confer hardness. Small blood vessels called haversian canals supply the bone with oxygen and nutrients. Cartilage is afirm bu flexible substance which is less rigid than bone. It consists of an organic matrix in which are embedded spherical cells called chondroblasts.
I think the correct answer would be the first option. The best method to use in order to measure the distance of star would be to calculate the variations in the position of the star due to movement of Earth in its orbit. The doppler shift which is what is being described in the last three options does not calculate the distance rather it calculates the relative velocity. The method used in measuring the distance was introduced by Edwin Hubble where he found that relative velocity of a body in space is directly proportional to the distance of that body from Earth.
Explanation:
It's superior vena cava and vena cava
