Consider two walls, A and B, with the same surface areas and the same temperature drops across their thicknesses. The ratio of their thermal conductivities is kA/kB=4 and the ratio of the wall thickness is LA/LB=2. The ratio of heat transfer rates through the walls qA/qB is:

(a) 0.5
(b) 1
(c) 2
(d) 4
(e) 8
(f) None of them

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.

Will you chech and finish these for me, because i am stumped with them.

Clothes dryer uses about 7 amps of current from a 240 volt line. how much power does it use?