What is the si unit of time?
a. second
b. minute
c. hourd.
day

A. Second

Explanation:

The Si unit of time is second

The answer is option A "second." The SI unit of time is a second other units of measure consist of mass, metre, temperature, and kilogram. A second is how you measure time because how 60 seconds equal a minute, 60 minutes equal a hour, 24 hours equal a day then so on.

Hope this helps.

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.