One of the three main functions of stems is to
a. carry out photosynthesis.
b. carry water and nutrients between roots and leaves.
c. store carbohydrates.
d. store water.

B

Explanation:

A is describing leaves

B is correct

C and D might be referring to roots or other storage modifications

the transfer for conduction is the heat transfering from the liquid to the spoon

the transfer for convection is the heat rising from the liquid to the air

the transfer for radiation is the heat going through the sides of the cup and to the air

at least that is what i would do