The answer is b, I hope this helps you
Answer:
6.5 × 10¹⁵/ cm³
Explanation:
Thinking process:
The relation 
With the expression Ef - Ei = 0.36 × 1.6 × 10⁻¹⁹
and ni = 1.5 × 10¹⁰
Temperature, T = 300 K
K = 1.38 × 10⁻²³
This generates N₀ = 1.654 × 10¹⁶ per cube
Now, there are 10¹⁶ per cubic centimeter
Hence, 
Answer:
W = 2695.14 lb
Explanation:
given,
side of cube = 3 ft
density of the cube = 3.1 slugs/ft³
we know,

mass = density x volume
volume = 3³ = 27 ft³
mass = 3.1 x 27
m = 83.7 slugs.
weight calculation
converting mass from slug to pound
weight of 1 slug is equal to 32.2 lb
now,
weight of the cube is equal to
W = 83.7 slugs x 32.2 lb/slug
W = 2695.14 lb
hence, weight is equal to W = 2695.14 lb
Answer:
Head loss=0.00366 ft
Explanation:
Given :Water flow rate Q=0.15 
= 6 inch=0.5 ft
=2 inch=0.1667 ft
As we know that Q=AV

So 

=0.687 ft/sec
We know that Head loss due to sudden contraction

If nothing is given then take K=0.5
So head loss
=0.00366 ft
So head loss=0.00366 ft
Answer:
Cement is largely made up of calcium oxide. Cement can harden in the gastrointestinal tract and cause obstruction. Inhaling cement dust can cause coughing, wheezing, and difficulty breathing. The best prevention is to avoid or limit contact with cement.
Explanation: