Match the following items. 1.
uses a lens to gather and focus light
refracting telescope
2. separates starlight into wavelengths
radio telescopes
3. pick up faint-lighted stars
spectrograph
4. see binary stars
giant refractors
5. see behind nebulae dust
giant reflectors

i believe it is c.) 1575 j.

it is stable as it is in group 0 which have full outer shells of electrons

intermolecular forces are the forces between molecules or particles.

there are two kinds of van der waals forces: weak london dispersion forces and stronger dipole-dipole forces.

in molecule of water there are dipole-dipole forces between negatively charged oxygen from one molecule of water and positively charger hydrogen of another molecule of water.

hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom (h), covalently bound to a highly electronegative atom such as flourine (f), oxygen (o) and nitrogen (n) atoms.