Answer:
38:81
Step-by-step explanation:
There are a total of 81 Astronauts in the space program.
Out of these, 43 are in outer space.
We are to determine the ratio of the number of astronauts on Earth to the total number of astronauts.
Number of Astronauts on Earth = Total Number - Number in Outer Space
=81-43 = 38
Therefore:
Number of astronauts on Earth : The total number of astronauts. = 38:81
Answer:
See Explanation
Step-by-step explanation:
<em>Question like this are better answered if there are list of options; However, I'll simplify as far as the expression can be simplified</em>
Given

Required
Simplify

Represent
with a
Represent
with b
The expression becomes

Factorize



Recall that

The expression
becomes

..............................................................................................................................
In trigonometry

Subtract
from both sides


..............................................................................................................................
Substitute 1 for
in 

Open Bracket
------------------This is an equivalence

Solving further;
................................................................................................................................
In trigonometry


Substitute the expressions for secx and tanx
................................................................................................................................
becomes

Open bracket


Add Fraction
------------------------ This is another equivalence
................................................................................................................................
In trigonometry

Make
the subject of formula

................................................................................................................................
Substitute the expressions for
for 

Open bracket

---------------------- This is another equivalence
Answer:
28.5 miles per gallon
Step-by-step explanation:
399 miles / 14 gallons
= 28.5 miles/1 gallon
1 gallon per 28.5 miles
3600 squared is 60 I believe