Answer:
a)
, b) 
Explanation:
a) The equation for vertical velocity is obtained by deriving the function with respect to time:

The velocities at given instants are, respectivelly:


Since each student emits 100 W, so 170 students will emit:
total heat = 100 W * 170 = 17,000 W
Convert minutes to seconds:
time = 50 min * (60 s / min) = 3000 s
The energy is therefore:
E = 17,000 W * 3000 s
<span>E = 51 x 10^6 J = 51 MJ</span>
Langerhans cells exist on the surface of the skin. They help to protect you by keeping dangerous microbes from entering your body. Langerhans cells do this in two very different ways: by protecting your skin from infection and also by stimulating allergic reactions.
Forces that are equal in size but opposite in direction and do not cause a change in an object's movement are called balanced forces.
forces that aren't equal in size and do cause a change in movement (what it seems like you're asking for) are called UNBALANCED FORCES
so answer (in case that wasn't clear, as I'm tired) : unbalanced forces
Answer: It is both B and D
Select all that apply.
At night, thermal energy moves _____.
from space to the atmosphere
from the land to the atmosphere
from the atmosphere to the land
from the atmosphere to space