Which term refers to large groupings of stars a. nebulas b. galaxies c. binary stars d. star clusters

D. Star Clusters

Explanation:

A star cluster is a large group of stars. A star cluster can be open cluster or a globular cluster. An open cluster has about 100 to 1000 of stars loosely grouped together. It usually contains new stars.

A globular cluster has thousands of stars tightly grouped together. It usually contains old stars.  

A galaxy is a group of stars, dust and gases.

Binary stars are two stars rotating about a common center of mass.

Nebulae are stellar nurseries where stars are born.

D. Star Clusters

Explanation:

its in the name read it

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.