Well there are infact 2 walls. There is the atrial septum which separates right and left atriums. And there is the ventricular septum which separates the right and left ventricles.
I'm not quite sure if if it's asking you for two or one answer, but maybe writing both shall help.
Answer:
Option D
Explanation:
Options for the question
A)import seeds produced in the southern hemisphere.
B)plant the flowers out-of doors in november.
C)keep the plants in a warm growing environment.
D)expose the plants to an hour of light in the middle of each night until the end of april.
Solution
Since Chrysanthemum is a short-day plant, its flower mainly develop during night and hence they require long nights of 11 to 12 hours. Blackout system is sometimes used to induce flowering.Flowering can be delayed by regulating both light and temperature. this is done by exposing plants for a short period of time to light (can be artificial) and to some source of heat that produces 85° F or higher temperature.
Thus if flowers are required in month of may, flowering can be delayed by exposing Chrysanthemums plant to light and heat source during night time
Option D is correct
I would say B) because the rest dosnt quite make sense to me and A) the gravity of the sun would still be the same despite the shape if we have an triangle block and an sphere then drop the they are going to drop at the same speed the gravity is not going to sphere is not going to fall faster