16. The high surface temperature of Venus is due to [ the greenhouse effect / volcanic heat release ]. 17. In planetary sciences, a [ chasma / corona ] is an oval-shaped feature.

18. Because of the
[ high temperature / low escape velocity ], atoms in Mercury’s atmosphere just bounce around and eventually disappear into space.

19. Mercury’s period of rotation is exactly [ one third / two thirds ] of its orbital period.

20. Mercury is [ tidally coupled / antipodal ] to the Sun, thus affecting its rotation.

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3

answer; capital earns interest; entrepreneurship receives a profit or incurs a loss;

answer///carbon;