Consider a kirby-bauer disk-diffusion assay. if you put penicillin and streptomycin disks adjacent to one another, the zone of inhibition is greater than that obtained by either disk alone. this is an example of
a. rna interference
b. mutual exclusion
c. synergism
d. antagonism

This is an example of synergism.

Explanation:

synergism is the motion of two or more than two trans- acting agents that given at a same time which is greater than the sum of activity had those agents if given separately. They are steroid receptors, which acts as response for saturating concentration of the steroids.  The synergism of the steroid receptors among themselves or with anti-infective factors at saturating concentration of steroid has showed to be very important component for steroid regulated gene transcription.

1: most common garden plants prefer loam — soils with a balance of different-sized mineral particles (approximately 40% sand, 40% silt, and 20% clay) with ample organic matter and pore space. however, some plants grow better in sandy soils, while others are well-adapted to clay soils.

2: available water capacity is the maximum amount of plant available water a soil can provide. it is an indicator of a soil's ability to retain water and make it sufficiently available for plant use. available water capacity is the water held in soil between its field capacity and permanent wilting point.

3: it is the same for all living things (plants and animals). it also includes very tiny organisms that our eyes cannot see. they are known as microorganisms, and include viruses, bacteria and fungi.