Question

out of two solar cookers one was covered with plain glass slab and other was left open which one is more efficient and why​

Answer 1

A solar cooker covered by a plane glass slab will be more efficient.
This is because glass slab does not allow the heat radiation to escape from the solar cooker and hence the temperature of the solar cooker with glass slab increases more than the temperature of the solar cooker which is left open.

Hope it helps you.
Mark it as brainlist.

Answer 2

here's your answer :---

out of the two solar cookers,the glass slab covered cooker will be more efficient. this is because when sunlight enters the solar cooker then the glass slab does not allow the light rays to go back.this results in the continuous increasing in temperature in the solar cooker and the food will cooked properly.

hope this helps.

#PLZ MARK AS BRAINLIEST