The answer is A, biogeochemical cycles.
1s2 2s2 2p2 i hope this helps
The given question is incomplete. The complete question is :
In each row check off the boxes that apply to the underlined reactant. The underlined reactant acts as a... (check all that apply)
1. 
here underlined is 
A. Brønsted-Lowry acid
B. Brønsted-Lowry base
C. Lewis acid
D. Lewis base
2. 
Here underlined is 
A. Brønsted-Lowry acid
B. Brønsted-Lowry base
C. Lewis acid
D. Lewis base
3. 
Here underlined is 
A. Brønsted-Lowry acid
B. Brønsted-Lowry base
C. Lewis acid
D. Lewis base
Answer: 1. Brønsted-Lowry acid
2. Lewis base
3. Brønsted-Lowry base
Explanation:
According to the Bronsted Lowry conjugate acid-base theory, an acid is defined as a substance which donates protons and a base is defined as a substance which accepts protons.
According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.
1. 
As
is donating a proton , it acts as a bronsted acid.
2. 
As
contains a lone pair of electron on nitrogen , it can easily donate electrons to
and act as lewi base.
3. 
As
is accepting a proton , it acts as a bronsted base.
Answer:
The mass ratio of zinc to sulfide is 85:42.
2.5559 kg of Zn are in 3.82 kg of ZnS.
Explanation:
a) Mass of zinc sulfide = 254 g
Mass of zinc in a zinc sulfide sample = 170 g
Mass of sulfide in zinc sulfide sample = x
254 g = 170 g+ x
x = 84 g
The mass ratio of zinc to sulfide:

b) Mass of zincsulfide sample = 3.83 kg
The mass ratio of zinc to sulfide is 85:42.
Let the mass of zinc and sulfide be 85x and 42x respectively:
85 x+ 42 x=3.82 kg
x =0.03007 kg
Mass of an zinc= 85x=85 × 0.03007 kg= 2.5559 kg
The answer is true the answer has to be 20 words long so true true true true true true