Gina designed a model to show the steps in the nebular theory of formation of planetary systems. which of these diagrams best represents the second step of gina's model?
a.) condensation and contraction of cloud do to gravity

b.) rotation of cloud of gas and dust

c.) formation of planet

d.) fusion of gas and dust at the center to form the sun

B.) rotation of cloud of gas and dust

Explanation:

According to Nebular theory, the sun and the planets were formed from the Solar Nebula. Initially a fragment of the molecular cloud of dust and gases collapsed under its own weight. This contracted portion starts to rotate until a high enough temperature and pressure causes the nuclear fusion reaction in the core to start and form the Sun. The planets were formed from rest of the part of the cloud.

Thus, the second step of Gina's model should be B.) rotation of cloud of gas and dust .

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.