Can someone help me with two questions please? Both questions are multiple choice. The questions are in the pictures below. Thank you!

Sydney drew a flow chart to illustrate the nitrogen cycle. which labels best complete the flow chart? x: producers undergo photosynthesis. y: nitrogen compounds are released into the air. x: nitrogen compounds are released into the air. y: producers undergo photosynthesis. x: free nitrogen is in the atmosphere. y: producers absorb nitrogen compounds through their roots. x: producers absorb nitrogen compounds through their roots. y: free nitrogen is in the atmosphere.

Surrounded by microtubules, located near the nucleus. (don't try to google it) (give answer only if u know)

During the winter, this species of fox has white fur, but in the summer, it has brown fur. what environmental change may have lead to this fox's fur color? snow cover increase in sun's brightness volcanic eruption global warming