Ferns reproduce with spores which existed the longest in Earth history.
Gymnosperms reproduce with cones and has needle-like, waxy leaves.
Angiosperms reproduce with flowers and newest type of plant in Earth history.
<h3>How ferns, gymnosperm and angiosperm reproduce?</h3>
Ferns reproduce with spores that existed the longest in Earth, gymnosperms reproduce through the formation of cones having needle-like, waxy leaves whereas angiosperms reproduce with flowers which turns into seed. The newest type of plant in Earth history is also belongs to this group.
Learn more about spore here: brainly.com/question/1022692
The center of a plant cell is a nucleus!
Answer:

Explanation:
The atomic weight of oxygen = 15.9994 g
This mass corresponds to 1 mole of the oxygen atoms.
Thus,
15.9994 g mass of oxygen contains
atoms of oxygen.
1.4 kg = 1400 g ( 1 kg = 1000 g)
So,
1400 g mass of oxygen contains
atoms of oxygen.
Number of atoms in 1400 g of oxygen = 
Also, 1 atom of oxygen contains 8 protons
Charge of 1 proton = + 
So, Charge on 1 atom of oxygen = 
Thus,
Charge on
atoms of oxygen = 
Thus, positive charge in 1.4 kg of oxygen = 
Answer:
B. Tell the instructor
Explanation:
Always to the instructor about any accidents happens in a lab.