Answer:
Step-by-step explanation:
Rising 30 feet for every 400 feet of track is not a very large angle of elevation. We set this up as a right triangle to use right triangle trig to solve for the missing angle. The height is 30 and the hypotenuse is 400. The height is the side opposite the angle in question, and the hypotenuse is the hypotenuse! This is the sin ratio. Setting up the ratio using our info:

When you are looking for a missing angle measure, as we are here, use the 2nd-->sin buttons to find the inverse of sin, which looks like this:

Enter in the fraction 30/400 after the parenthesis and then hit enter to get the angle measure of 4.3 degrees.
Answer:
20
Step-by-step explanation:
Answer:
≈13degrees
Step-by-step explanation:
It is given that Two cities A and B are 1400km apart and lie on the same N-S line. The latitude of city A is 23 Degrees. Then,
Using the formula,
where s is the distance between the two cities and r is the radius of the earth,thus substituting the values, we get

⇒
Therefore, 
⇒
⇒
Thus, the latitude of B is=12.53 degrees≈13degrees
If A and B are independent, then
.
a.



b. I'm guessing the ? is supposed to stand for intersection. We can use DeMorgan's law for complements here:



c. DeMorgan's law can be used here too:


