Grams should be an appropriate unit to measure an apple. It is a metric unit and is usually used for the mass of an object
Because they have no competitors in any echological niche
This is referred to as: spontaneous recovery
Spontaneous recovery is a theory of learning and memory which involves unexpected and recurrence of a conditioned response after a period of reduced response or delay. Spontaneous recovery is associated with classical conditioning and operant conditioning. Extinction will happen quickly after a spontaneous recovery, if the conditioned and unconditioned stimulus is not connected.
Answer:
chloroplast i think , i may b wrong