A) d+q=20
0.1d+0.25q=4.40 Let's just read what this says: first, # of dimes (d) plus # of quarters (q) is 20.The second equation can be called the VALUE EQUATION; it says that one tenth of a dollar ($0.10) times the # of dimes is part of the total monetary value, and that one quarter of a dollar ($0.25) times the # of 'quarter' coins is the other part of this stash, and it totals $4.40. VOTE FOR A.
B and C for the first two
Answer:

Step-by-step explanation:
As the numbers are only between 1 and 30
Total number of possible combinations = 30×30×30 = 27000
If there are 100 attempts then

∴ Probability someone can guess the correct combination given 100 attempts is 
Answer:
#1. 1232 feet per minute
#2. $14.81 per second
#3. 46.93 feet per second
Hope This Helps!
And that it's right!
Answer:
5.1 and 5.05
Not really much to explain. Still, hope this helped!
P.S. (5.2 is more than 5.03, btw)