Which of the following is an example of heat transfer by conduction?

a. the upstairs of a house being warmer than the downstairs

b. burning your finger on a hot match

c. the sun warming your skin

d. being warmed by a fire on a cold night

Conduction is when heat is transfered because surfaces are touching
convection is transfer through a fluid or gas like water or air

A is convection
B is when you touch the match, conduction
C is convection
D. you aren't touching the fire so convection

B is answer

m=9

step-by-step explanation:

7m+8=71 subtract   8 from 71 which is 63 than divide it by 7m   equal 9.